[Note that this file is a concatenation of more than one RFC.]





Internet Engineering Task Force (IETF)                         A. Newton
Request for Comments: 7480                                          ARIN
Category: Standards Track                                    B. Ellacott
ISSN: 2070-1721                                                    APNIC
                                                                N. Kong
                                                                  CNNIC
                                                             March 2015


      HTTP Usage in the Registration Data Access Protocol (RDAP)

Abstract

  This document is one of a collection that together describes the
  Registration Data Access Protocol (RDAP).  It describes how RDAP is
  transported using the Hypertext Transfer Protocol (HTTP).  RDAP is a
  successor protocol to the very old WHOIS protocol.  The purpose of
  this document is to clarify the use of standard HTTP mechanisms for
  this application.

Status of This Memo

  This is an Internet Standards Track document.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Further information on
  Internet Standards is available in Section 2 of RFC 5741.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc7480.

Copyright Notice

  Copyright (c) 2015 IETF Trust and the persons identified as the
  document authors.  All rights reserved.

  This document is subject to BCP 78 and the IETF Trust's Legal
  Provisions Relating to IETF Documents
  (http://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.



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Table of Contents

  1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
  2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
  3.  Design Intents  . . . . . . . . . . . . . . . . . . . . . . .   5
  4.  Queries . . . . . . . . . . . . . . . . . . . . . . . . . . .   5
    4.1.  HTTP Methods  . . . . . . . . . . . . . . . . . . . . . .   5
    4.2.  Accept Header . . . . . . . . . . . . . . . . . . . . . .   5
    4.3.  Query Parameters  . . . . . . . . . . . . . . . . . . . .   6
  5.  Types of HTTP Response  . . . . . . . . . . . . . . . . . . .   6
    5.1.  Positive Answers  . . . . . . . . . . . . . . . . . . . .   6
    5.2.  Redirects . . . . . . . . . . . . . . . . . . . . . . . .   6
    5.3.  Negative Answers  . . . . . . . . . . . . . . . . . . . .   7
    5.4.  Malformed Queries . . . . . . . . . . . . . . . . . . . .   7
    5.5.  Rate Limits . . . . . . . . . . . . . . . . . . . . . . .   7
    5.6.  Cross-Origin Resource Sharing (CORS)  . . . . . . . . . .   8
  6.  Extensibility . . . . . . . . . . . . . . . . . . . . . . . .   8
  7.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
  8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
    8.1.  RDAP Extensions Registry  . . . . . . . . . . . . . . . .   9
  9.  Internationalization Considerations . . . . . . . . . . . . .  10
    9.1.  URIs and IRIs . . . . . . . . . . . . . . . . . . . . . .  10
    9.2.  Language Identifiers in Queries and Responses . . . . . .  10
    9.3.  Language Identifiers in HTTP Headers  . . . . . . . . . .  10
  10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
    10.1.  Normative References . . . . . . . . . . . . . . . . . .  11
    10.2.  Informative References . . . . . . . . . . . . . . . . .  12
  Appendix A.  Protocol Example . . . . . . . . . . . . . . . . . .  13
  Appendix B.  Cache Busting  . . . . . . . . . . . . . . . . . . .  13
  Appendix C.  Bootstrapping and Redirection  . . . . . . . . . . .  14
  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . 15
  Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16



















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1.  Introduction

  This document describes the usage of the Hypertext Transfer Protocol
  (HTTP) [RFC7230] for the Registration Data Access Protocol (RDAP).
  The goal of this document is to tie together usage patterns of HTTP
  into a common profile applicable to the various types of directory
  services serving registration data using practices informed by the
  Representational State Transfer (REST) [REST] architectural style.
  By giving the various directory services common behavior, a single
  client is better able to retrieve data from directory services
  adhering to this behavior.

  Registration data expected to be presented by this service is
  Internet resource registration data -- registration of domain names
  and Internet number resources.  This data is typically provided by
  WHOIS [RFC3912] services, but the WHOIS protocol is insufficient to
  modern registration data service requirements.  A replacement
  protocol is expected to retain the simple transactional nature of
  WHOIS, while providing a specification for queries and responses,
  redirection to authoritative sources, support for Internationalized
  Domain Names (IDNs) [RFC5890], and support for localized registration
  data such as addresses and organization or person names.

  In designing these common usage patterns, this document introduces
  considerations for a simple use of HTTP.  Where complexity may
  reside, it is the goal of this document to place it upon the server
  and to keep the client as simple as possible.  A client
  implementation should be possible using common operating system
  scripting tools (e.g., bash and wget).

  This is the basic usage pattern for this protocol:

  1.  A client determines an appropriate server to query along with the
      appropriate base Uniform Resource Locator (URL) to use in such
      queries.  [RFC7484] describes one method to determine the server
      and the base URL.  See Appendix C for more information.

  2.  A client issues an HTTP (or HTTPS) query using GET [RFC7231].  As
      an example, a query URL for the network registration 192.0.2.0
      might be

         http://example.com/rdap/ip/192.0.2.0

      [RFC7482] details the various queries used in RDAP.







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  3.  If the receiving server has the information for the query, it
      examines the Accept header field of the query and returns a 200
      response with a response entity appropriate for the requested
      format.  [RFC7483] details a response in JavaScript Object
      Notation (JSON).

  4.  If the receiving server does not have the information for the
      query but does have knowledge of where the information can be
      found, it will return a redirection response (3xx) with the
      Location header field containing an HTTP(S) URL pointing to the
      information or another server known to have knowledge of the
      location of the information.  The client is expected to requery
      using that HTTP URL.

  5.  If the receiving server does not have the information being
      requested and does not have knowledge of where the information
      can be found, it returns a 404 response.

  6.  If the receiving server will not answer a request for policy
      reasons, it will return an error response (4xx) indicating the
      reason for giving no answer.

  It is not the intent of this document to redefine the meaning and
  semantics of HTTP.  The purpose of this document is to clarify the
  use of standard HTTP mechanisms for this application.

2.  Terminology

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
  document are to be interpreted as described in [RFC2119].

  As is noted in "Security and Stability Advisory Committee (SSAC)
  Report on WHOIS Terminology and Structure" [SAC-051], the term
  "WHOIS" is overloaded, often referring to a protocol, a service, and
  data.  In accordance with [SAC-051], this document describes the base
  behavior for an RDAP.  [SAC-051] describes a protocol profile of RDAP
  for Domain Name Registries (DNRs), the Domain Name Registration Data
  Access Protocol (DNRD-AP).

  In this document, an RDAP client is an HTTP user agent performing an
  RDAP query, and an RDAP server is an HTTP server providing an RDAP
  response.  RDAP query and response formats are described in [RFC7482]
  and [RFC7483], while this document describes how RDAP clients and
  servers use HTTP to exchange queries and responses.  [RFC7481]
  describes security considerations for RDAP.





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3.  Design Intents

  There are a few design criteria this document attempts to meet.

  First, each query is meant to require only one path of execution to
  obtain an answer.  A response may contain an answer, no answer, or a
  redirect, and clients are not expected to fork multiple paths of
  execution to make a query.

  Second, the semantics of the request/response allow for future and/or
  non-standard response formats.  In this document, only a JSON
  [RFC7159] response media type is noted, with the response contents to
  be described separately (see [RFC7483]).  This document only
  describes how RDAP is transported using HTTP with this format.

  Third, this protocol is intended to be able to make use of the range
  of mechanisms available for use with HTTP.  HTTP offers a number of
  mechanisms not described further in this document.  Operators are
  able to make use of these mechanisms according to their local policy,
  including cache control, authorization, compression, and redirection.
  HTTP also benefits from widespread investment in scalability,
  reliability, and performance, as well as widespread programmer
  understanding of client behaviors for web services styled after REST
  [REST], reducing the cost to deploy Registration Data Directory
  Services and clients.  This protocol is forward compatible with HTTP
  2.0.

4.  Queries

4.1.  HTTP Methods

  Clients use the GET method to retrieve a response body and use the
  HEAD method to determine existence of data on the server.  Clients
  SHOULD use either the HTTP GET or HEAD methods (see [RFC7231]).
  Servers are under no obligation to support other HTTP methods;
  therefore, clients using other methods will likely not interoperate
  properly.

  Clients and servers MUST support HTTPS to support security services.

4.2.  Accept Header

  To indicate to servers that an RDAP response is desired, clients
  include an Accept header field with an RDAP-specific JSON media type,
  the generic JSON media type, or both.  Servers receiving an RDAP
  request return an entity with a Content-Type header containing the
  RDAP-specific JSON media type.




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  This specification does not define the responses a server returns to
  a request with any other media types in the Accept header field, or
  with no Accept header field.  One possibility would be to return a
  response in a media type suitable for rendering in a web browser.

4.3.  Query Parameters

  Servers MUST ignore unknown query parameters.  Use of unknown query
  parameters for cache busting is described in Appendix B.

5.  Types of HTTP Response

  This section describes the various types of responses a server may
  send to a client.  While no standard HTTP response code is forbidden
  in usage, this section defines the minimal set of response codes in
  common use by servers that a client will need to understand.  While
  some clients may be constructed with simple tooling that does not
  account for all of these response codes, a more robust client
  accounting for these codes will likely provide a better user
  experience.  It is expected that usage of response codes and types
  for this application not defined here will be described in subsequent
  documents.

5.1.  Positive Answers

  If a server has the information requested by the client and wishes to
  respond to the client with the information according to its policies,
  it returns that answer in the body of a 200 (OK) response (see
  [RFC7231]).

5.2.  Redirects

  If a server wishes to inform a client that the answer to a given
  query can be found elsewhere, it returns either a 301 (Moved
  Permanently) response code to indicate a permanent move or a 302
  (Found), 303 (See Other), or 307 (Temporary Redirect) response code
  to indicate a non-permanent redirection, and it includes an HTTP(S)
  URL in the Location header field (see [RFC7231]).  The client is
  expected to issue a subsequent request to satisfy the original query
  using the given URL without any processing of the URL.  In other
  words, the server is to hand back a complete URL, and the client
  should not have to transform the URL to follow it.  Servers are under
  no obligation to return a URL conformant to [RFC7482].

  For this application, such an example of a permanent move might be a
  Top-Level Domain (TLD) operator informing a client the information





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  being sought can be found with another TLD operator (i.e., a query
  for the domain bar in foo.example is found at
  http://foo.example/domain/bar).

  For example, if the client uses

     http://serv1.example.com/weirds/domain/example.com

  the server redirecting to

     https://serv2.example.net/weirds2/

  would set the Location: field to the value

     https://serv2.example.net/weirds2/domain/example.com

5.3.  Negative Answers

  If a server wishes to respond that it has an empty result set (that
  is, no data appropriately satisfying the query), it returns a 404
  (Not Found) response code.  Optionally, it MAY include additional
  information regarding the negative answer in the HTTP entity body.

  If a server wishes to inform the client that information about the
  query is available, but cannot include the information in the
  response to the client for policy reasons, the server MUST respond
  with an appropriate response code out of HTTP's 4xx range.  A client
  MAY retry the query if that is appropriate for the respective
  response code.

5.4.  Malformed Queries

  If a server receives a query that it cannot interpret as an RDAP
  query, it returns a 400 (Bad Request) response code.  Optionally, it
  MAY include additional information regarding this negative answer in
  the HTTP entity body.

5.5.  Rate Limits

  Some servers apply rate limits to deter address scraping and other
  abuses.  When a server declines to answer a query due to rate limits,
  it returns a 429 (Too Many Requests) response code as described in
  [RFC6585].  A client that receives a 429 response SHOULD decrease its
  query rate and honor the Retry-After header field if one is present.
  Servers may place stricter limits upon clients that do not honor the
  Retry-After header.  Optionally, the server MAY include additional
  information regarding the rate limiting in the HTTP entity body.




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  Note that this is not a defense against denial-of-service (DoS)
  attacks, since a malicious client could ignore the code and continue
  to send queries at a high rate.  A server might use another response
  code if it did not wish to reveal to a client that rate limiting is
  the reason for the denial of a reply.

5.6.  Cross-Origin Resource Sharing (CORS)

  When responding to queries, it is RECOMMENDED that servers use the
  Access-Control-Allow-Origin header field, as specified by
  [W3C.REC-cors-20140116].  A value of "*" is suitable when RDAP is
  used for public resources.

  This header (often called the CORS header) helps in-browser web
  applications by lifting the "same-origin" restriction (i.e., a
  browser may load RDAP client code from one web server but query
  others for RDAP data).

  By default, browsers do not send cookies when cross origin requests
  are allowed.  Setting the Access-Control-Allow-Credentials header
  field to "true" will send cookies.  Use of the
  Access-Control-Allow-Credentials header field is NOT RECOMMENDED.

6.  Extensibility

  For extensibility purposes, this document defines an IANA registry
  for prefixes used in JSON [RFC7159] data serialization and URI path
  segments (see Section 8).

  Prefixes and identifiers SHOULD only consist of the alphabetic US-
  ASCII characters A through Z in both uppercase and lowercase, the
  numerical digits 0 through 9, and the underscore character, and they
  SHOULD NOT begin with an underscore character, numerical digit, or
  the characters "xml".  The following describes the production of JSON
  names in ABNF [RFC5234].

    name = ALPHA *( ALPHA / DIGIT / "_" )

                      Figure 1: ABNF for JSON Names

  This restriction is a union of the Ruby programming language
  identifier syntax and the XML element name syntax and has two
  purposes.  First, client implementers using modern programming
  languages such as Ruby or Java can use libraries that automatically
  promote JSON names to first-order object attributes or members.
  Second, a clean mapping between JSON and XML is easy to accomplish
  using these rules.




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7.  Security Considerations

  This document does not pose strong security requirements to the RDAP
  protocol.  However, it does not restrict against the use of security
  mechanisms offered by the HTTP protocol.  It does require that RDAP
  clients and servers MUST support HTTPS.

  This document makes recommendations for server implementations
  against DoS (Section 5.5) and interoperability with existing security
  mechanisms in HTTP clients (Section 5.6).

  Additional security considerations to the RDAP protocol are covered
  in [RFC7481].

8.  IANA Considerations

8.1.  RDAP Extensions Registry

  IANA has created a new category in the protocol registries labeled
  "Registration Data Access Protocol (RDAP)", and within that category,
  has established a URL-referenceable, stand-alone registry labeled
  "RDAP Extensions".  The purpose of this registry is to ensure
  uniqueness of extension identifiers.  The extension identifier is
  used as a prefix in JSON names and as a prefix of path segments in
  RDAP URLs.

  The production rule for these identifiers is specified in Section 6.

  In accordance with [RFC5226], the IANA policy for assigning new
  values, shall be Specification Required: values and their meanings
  must be documented in an RFC or in some other permanent and readily
  available reference, in sufficient detail that interoperability
  between independent implementations is possible.

  The following is a template for an RDAP extension registration:

     Extension identifier: the identifier of the extension

     Registry operator: the name of the registry operator

     Published specification: RFC number, bibliographical reference, or
     URL to a permanent and readily available specification

     Person & email address to contact for further information: The
     names and email addresses of individuals to contact regarding this
     registry entry





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     Intended usage: brief reasons for this registry entry (as defined
     by [RFC5226]).

  The following is an example of a registration in the RDAP extension
  registry:

     Extension identifier: lunarNic

     Registry operator: The Registry of the Moon, LLC

     Published specification: http://www.example/moon_apis/rdap

     Person & email address to contact for further information:
     Professor Bernardo de la Paz <[email protected]>

     Intended usage: COMMON

9.  Internationalization Considerations

9.1.  URIs and IRIs

  Clients can use Internationalized Resource Identifiers (IRIs)
  [RFC3987] for internal use as they see fit but MUST transform them to
  URIs [RFC3986] for interaction with RDAP servers.  RDAP servers MUST
  use URIs in all responses, and again clients can transform these URIs
  to IRIs for internal use as they see fit.

9.2.  Language Identifiers in Queries and Responses

  Under most scenarios, clients requesting data will not signal that
  the data be returned in a particular language or script.  On the
  other hand, when servers return data and have knowledge that the data
  is in a language or script, the data SHOULD be annotated with
  language identifiers whenever they are available, thus allowing
  clients to process and display the data accordingly.

  [RFC7483] provides such a mechanism.

9.3.  Language Identifiers in HTTP Headers

  Given the description of the use of language identifiers in
  Section 9.2, unless otherwise specified, servers SHOULD ignore the
  HTTP [RFC7231] Accept-Language header field when formulating HTTP
  entity responses, so that clients do not conflate the Accept-Language
  header with the 'lang' values in the entity body.






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  However, servers MAY return language identifiers in the Content-
  Language header field so as to inform clients of the intended
  language of HTTP layer messages.

10.  References

10.1.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997,
             <http://www.rfc-editor.org/info/rfc2119>.

  [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
             Resource Identifier (URI): Generic Syntax", STD 66, RFC
             3986, January 2005,
             <http://www.rfc-editor.org/info/rfc3986>.

  [RFC3987]  Duerst, M. and M. Suignard, "Internationalized Resource
             Identifiers (IRIs)", RFC 3987, January 2005,
             <http://www.rfc-editor.org/info/rfc3987>.

  [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
             IANA Considerations Section in RFCs", BCP 26, RFC 5226,
             May 2008, <http://www.rfc-editor.org/info/rfc5226>.

  [RFC6585]  Nottingham, M. and R. Fielding, "Additional HTTP Status
             Codes", RFC 6585, April 2012,
             <http://www.rfc-editor.org/info/rfc6585>.

  [RFC7230]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
             Protocol (HTTP/1.1): Message Syntax and Routing", RFC
             7230, June 2014, <http://www.rfc-editor.org/info/rfc7230>.

  [RFC7231]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
             Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
             June 2014, <http://www.rfc-editor.org/info/rfc7231>.

  [RFC7481]  Hollenbeck, S. and N. Kong, "Security Services for the
             Registration Data Access Protocol (RDAP)", RFC 7481,
             February 2015, <http://www.rfc-editor.org/info/rfc7481>.

  [RFC7482]  Newton, A. and S. Hollenbeck, "Registration Data Access
             Protocol (RDAP) Query Format", RFC 7482, February 2015,
             <http://www.rfc-editor.org/info/rfc7482>.

  [RFC7483]  Newton, A. and S. Hollenbeck, "JSON Responses for the
             Registration Data Access Protocol (RDAP)", RFC 7483,
             February 2015, <http://www.rfc-editor.org/info/rfc7483>.



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  [RFC7484]  Blanchet, M., "Finding the Authoritative Registration Data
             (RDAP) Service", RFC 7484, February 2015,
             <http://www.rfc-editor.org/info/rfc7484>.

  [W3C.REC-cors-20140116]
             Kesteren, A., "Cross-Origin Resource Sharing", W3C
             Recommendation, REC-cors-20140116, January 2014,
             <http://www.w3.org/TR/2014/REC-cors-20140116/>.

10.2.  Informative References

  [REST]     Fielding, R. and R. Taylor, "Principled Design of the
             Modern Web Architecture", ACM Transactions on Internet
             Technology, Vol. 2, No. 2, May 2002.

  [RFC3912]  Daigle, L., "WHOIS Protocol Specification", RFC 3912,
             September 2004, <http://www.rfc-editor.org/info/rfc3912>.

  [RFC5234]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
             Specifications: ABNF", STD 68, RFC 5234, January 2008,
             <http://www.rfc-editor.org/info/rfc5234>.

  [RFC5890]  Klensin, J., "Internationalized Domain Names for
             Applications (IDNA): Definitions and Document Framework",
             RFC 5890, August 2010,
             <http://www.rfc-editor.org/info/rfc5890>.

  [RFC7159]  Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
             Interchange Format", RFC 7159, March 2014,
             <http://www.rfc-editor.org/info/rfc7159>.

  [SAC-051]  Piscitello, D., Ed., "SSAC Report on Domain Name WHOIS
             Terminology and Structure", A report from the ICANN
             Security and Stability Advisory Committee (SSAC),
             September 2011.

  [lacnic-joint-whois]
             LACNIC, "Joint Whois", December 2005,
             <ftp://anonymous@ftp.registro.br/pub/gter/
             gter20/02-jwhois-lacnic.pdf>.











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Appendix A.  Protocol Example

  To demonstrate typical behavior of an RDAP client and server, the
  following is an example of an exchange, including a redirect.  The
  data in the response has been elided for brevity, as the data format
  is not described in this document.  The media type used here is
  described in [RFC7483].

  An example of an RDAP client and server exchange:

    Client:
        <TCP connect to rdap.example.com port 80>
        GET /rdap/ip/203.0.113.0/24 HTTP/1.1
        Host: rdap.example.com
        Accept: application/rdap+json

    rdap.example.com:
        HTTP/1.1 301 Moved Permanently
        Location: http://rdap-ip.example.com/rdap/ip/203.0.113.0/24
        Content-Length: 0
        Content-Type: application/rdap+json
        <TCP disconnect>

    Client:
        <TCP connect to rdap-ip.example.com port 80>
        GET /rdap/ip/203.0.113.0/24 HTTP/1.1
        Host:  rdap-ip.example.com
        Accept: application/rdap+json

    rdap-ip.example.com:
        HTTP/1.1 200 OK
        Content-Type: application/rdap+json
        Content-Length: 9001

        { ... }
        <TCP disconnect>

Appendix B.  Cache Busting

  Some HTTP [RFC7230] cache infrastructures do not adhere to caching
  standards adequately and could cache responses longer than is
  intended by the server.  To overcome these issues, clients can use an
  ad hoc and improbably used query parameter with a random value of
  their choosing.  As Section 4.3 instructs servers to ignore unknown
  parameters, this is compatible with the RDAP definition.






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  An example of using an unknown query parameter to bust caches:

    http://example.com/ip/192.0.2.0?__fuhgetaboutit=xyz123

  Use of an unknown parameter to overcome misbehaving caches is not
  part of any specification and is offered here for informational
  purposes.

Appendix C.  Bootstrapping and Redirection

  The traditional deployment model of WHOIS [RFC3912] does not provide
  a mechanism for determining the authoritative source for information.

  Some approaches have been implemented in the past, most notably the
  Joint WHOIS [lacnic-joint-whois] initiative.  However, among other
  shortcomings, Joint WHOIS is implemented using proxies and server-
  side referrals.

  These issues are solved in RDAP using HTTP redirects and
  bootstrapping.  Bootstrapping is discussed in [RFC7484].  In
  constrained environments, the processes outlined in [RFC7484] may not
  be viable, and there may be the need for servers acting as a
  "redirector".

  Redirector servers issue HTTP redirects to clients using a
  redirection table informed by [RFC7484].  Figure 2 diagrams a client
  using a redirector for bootstrapping.

                                     REDIRECTOR       ARIN
                                     RDAP             RDAP
                                       .               .
                                       |               |
       Q: 23.1.1.1? -----------------> |               |
                                       |               |
          <---------- HTTP 301 --------|               |
                 ('Try ARIN RDAP')     |               |
                                       |               |
                                                       |
         Q: 23.1.1.1? -------------------------------> |
                                                       |
            <---------- HTTP 200 --------------------- |
                   (JSON response is returned)         |
                                                       |
                                                       |
                                                       .

                Figure 2: Querying RDAP Data for 23.1.1.1




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  In some cases, particularly sub-delegations made between Regional
  Internet Registries (RIRs) known as "ERX space" and transfers of
  networks, multiple HTTP redirects will be issued.  Figure 3 shows
  such a scenario.

                         REDIRECTOR  LACNIC           ARIN
                         RDAP        RDAP             RDAP
                           .           .               .
       Q: 23.1.1.1? ---->  |           |               |
                           |           |               |
         <-- HTTP 301 ---  |           |               |
        ('Try LACNIC')     |           |               |
                           |           |               |
                           |           |               |
       Q: 23.1.1.1? -----------------> |               |
                                       |               |
          <---------- HTTP 301 --------|               |
                 ('Try ARIN RDAP')     |               |
                                       |               |
                                                       |
         Q: 23.1.1.1? -------------------------------> |
                                                       |
            <---------- HTTP 200 --------------------- |
                   (JSON response is returned)         |
                                                       |
                                                       |
                                                       .

     Figure 3: Querying RDAP Data for Data That Has Been Transferred

Acknowledgements

  John Levine provided text to tighten up the Accept header field usage
  and the text for the section on 429 responses.

  Marc Blanchet provided some clarifying text regarding the use of URLs
  with redirects, as well as very useful feedback during Working Group
  Last Call (WGLC).

  Normative language reviews were provided by Murray S. Kucherawy,
  Andrew Sullivan, Tom Harrison, Ed Lewis, and Alexander Mayrhofer.

  Jean-Phillipe Dionne provided text for the Security Considerations
  section.

  The concept of the redirector server informatively discussed in
  Appendix C was documented by Carlos M.  Martinez and Gerardo Rada of




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  LACNIC and Linlin Zhou of CNNIC and subsequently incorporated into
  this document.

  This document is the work product of the IETF's WEIRDS working group,
  of which Olaf Kolkman and Murray Kucherawy were chairs.

Authors' Addresses

  Andrew Lee Newton
  American Registry for Internet Numbers
  3635 Concorde Parkway
  Chantilly, VA  20151
  United States

  EMail: [email protected]
  URI:   http://www.arin.net


  Byron J. Ellacott
  Asia Pacific Network Information Centre
  6 Cordelia Street
  South Brisbane  QLD 4101
  Australia

  EMail: [email protected]
  URI:   http://www.apnic.net


  Ning Kong
  China Internet Network Information Center
  4 South 4th Street, Zhongguancun, Haidian District
  Beijing  100190
  China

  Phone: +86 10 5881 3147
  EMail: [email protected]















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=========================================================================





Internet Engineering Task Force (IETF)                     S. Hollenbeck
Request for Comments: 7481                                 Verisign Labs
Category: Standards Track                                        N. Kong
ISSN: 2070-1721                                                    CNNIC
                                                             March 2015


  Security Services for the Registration Data Access Protocol (RDAP)

Abstract

  The Registration Data Access Protocol (RDAP) provides "RESTful" web
  services to retrieve registration metadata from Domain Name and
  Regional Internet Registries.  This document describes information
  security services, including access control, authentication,
  authorization, availability, data confidentiality, and data integrity
  for RDAP.

Status of This Memo

  This is an Internet Standards Track document.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Further information on
  Internet Standards is available in Section 2 of RFC 5741.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc7481.

Copyright Notice

  Copyright (c) 2015 IETF Trust and the persons identified as the
  document authors.  All rights reserved.

  This document is subject to BCP 78 and the IETF Trust's Legal
  Provisions Relating to IETF Documents
  (http://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.





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Table of Contents

  1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
  2.  Conventions Used in This Document . . . . . . . . . . . . . .   2
    2.1.  Acronyms and Abbreviations  . . . . . . . . . . . . . . .   3
  3.  Information Security Services and RDAP  . . . . . . . . . . .   3
    3.1.  Access Control  . . . . . . . . . . . . . . . . . . . . .   3
    3.2.  Authentication  . . . . . . . . . . . . . . . . . . . . .   3
      3.2.1.  Federated Authentication  . . . . . . . . . . . . . .   4
    3.3.  Authorization . . . . . . . . . . . . . . . . . . . . . .   6
    3.4.  Availability  . . . . . . . . . . . . . . . . . . . . . .   6
    3.5.  Data Confidentiality  . . . . . . . . . . . . . . . . . .   7
    3.6.  Data Integrity  . . . . . . . . . . . . . . . . . . . . .   7
  4.  Privacy Threats Associated with Registration Data . . . . . .   8
  5.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
  6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
    6.1.  Normative References  . . . . . . . . . . . . . . . . . .  10
    6.2.  Informative References  . . . . . . . . . . . . . . . . .  11
  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  13
  Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

  The Registration Data Access Protocol (RDAP) is specified in multiple
  documents, including "Registration Data Access Protocol (RDAP) Query
  Format" [RFC7482], "JSON Responses for the Registration Data Access
  Protocol (RDAP)" [RFC7483], and "HTTP Usage in the Registration Data
  Access Protocol (RDAP)" [RFC7480].

  One goal of RDAP is to provide security services that do not exist in
  the WHOIS [RFC3912] protocol, including access control,
  authentication, authorization, availability, data confidentiality,
  and data integrity.  This document describes how each of these
  services is achieved by RDAP using features that are available in
  other protocol layers.  Additional or alternative mechanisms can be
  added in the future.  Where applicable, informative references to
  requirements for a WHOIS replacement service [RFC3707] are noted.

2.  Conventions Used in This Document

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
  document are to be interpreted as described in [RFC2119].








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2.1.  Acronyms and Abbreviations

     DNR: Domain Name Registry

     HTTP: Hypertext Transfer Protocol

     JSON: JavaScript Object Notation

     RDAP: Registration Data Access Protocol

     RIR: Regional Internet Registry

     TLS: Transport Layer Security

3.  Information Security Services and RDAP

  RDAP itself does not include native security services.  Instead, RDAP
  relies on features that are available in other protocol layers to
  provide needed security services, including access control,
  authentication, authorization, availability, data confidentiality,
  and data integrity.  A description of each of these security services
  can be found in "Internet Security Glossary, Version 2" [RFC4949].
  No requirements have been identified for other security services.

3.1.  Access Control

  WHOIS does not include specific features to control access to
  registration information.  As described in the following sections,
  RDAP includes features to identify, authenticate, and authorize
  clients, allowing server operators to control access to information
  based on a client's identity and associated authorizations.
  Information returned to a client can be clearly marked with a status
  value (see Section 10.2.2 of [RFC7483]) that identifies the access
  granted to the client.

3.2.  Authentication

  This section describes security authentication mechanisms and the
  need for authorization policies to include them.  It describes
  requirements for the implementations of clients and servers but does
  not dictate the policies of server operators.  For example, a server
  operator with no policy regarding differentiated or tiered access to
  data will have no authorization mechanisms and will have no need for
  any type of authentication.  A server operator with policies on
  differentiated access will have to construct an authorization scheme
  and will need to follow the specified authentication requirements.





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  WHOIS does not provide features to identify and authenticate clients.
  As noted in Section 3.1.4.2 of "Cross Registry Internet Service
  Protocol (CRISP) Requirements" [RFC3707], there is utility in
  allowing server operators to offer "varying degrees of access
  depending on policy and need."  Clients have to be identified and
  authenticated to provide that utility.

  RDAP's authentication framework needs to accommodate anonymous access
  as well as verification of identities using a range of authentication
  methods and credential services.  To that end, RDAP clients and
  servers MUST implement the authentication framework specified in
  "Hypertext Transfer Protocol (HTTP/1.1): Authentication" [RFC7235].
  The "basic" scheme can be used to send a client's user name and
  password to a server in plaintext, base64-encoded form.  The "digest"
  scheme can be used to authenticate a client without exposing the
  client's plaintext password.  If the "basic" scheme is used, HTTP
  over TLS [RFC2818] MUST be used to protect the client's credentials
  from disclosure while in transit (see Section 3.5).

  Servers MUST support either Basic or Digest authentication; they are
  not required to support both.  Clients MUST support both to
  interoperate with servers that support one or the other.  Servers may
  provide a login page that triggers HTTP authentication.  Clients
  should continue sending the HTTP authentication header once they
  receive an initial 401 (Unauthorized) response from the HTTP server
  as long as the scheme portion of the URL doesn't change.

  The Transport Layer Security protocol [RFC5246] includes an optional
  feature to identify and authenticate clients who possess and present
  a valid X.509 digital certificate [RFC5280].  Support for this
  feature is OPTIONAL.

  RDAP does not impose any unique server authentication requirements.
  The server authentication provided by TLS fully addresses the needs
  of RDAP.  In general, transports for RDAP must either provide a
  TLS-protected transport (e.g., HTTPS) or a mechanism that provides an
  equivalent level of server authentication.

  Work on HTTP authentication methods continues.  RDAP is designed to
  be agile enough to support additional methods as they are defined.

3.2.1.  Federated Authentication

  The traditional client-server authentication model requires clients
  to maintain distinct credentials for every RDAP server.  This
  situation can become unwieldy as the number of RDAP servers
  increases.  Federated authentication mechanisms allow clients to use
  one credential to access multiple RDAP servers and reduce client



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  credential management complexity.  RDAP MAY include a federated
  authentication mechanism that permits a client to access multiple
  RDAP servers in the same federation with one credential.

  Federated authentication mechanisms used by RDAP MUST be fully
  supported by HTTP.  OAuth, OpenID, Security Assertion Markup Language
  (SAML), and mechanisms based on Certification Authority (CA) are all
  possible approaches to provide federated authentication.  At the time
  of this document's publication, negotiation or advertisement of
  federated authentication services is still an undefined mechanism by
  the noted federated authentication protocols.  Developing this
  mechanism is beyond the scope of this document.

  The OAuth authorization framework [RFC6749] describes a method for
  users to access protected web resources without having to hand out
  their credentials.  Instead, clients are issued access tokens by
  authorization servers with the permission of the resource owners.
  Using OAuth, multiple RDAP servers can form a federation, and the
  clients can access any server in the same federation by providing one
  credential registered in any server in that federation.  The OAuth
  authorization framework is designed for use with HTTP and thus can be
  used with RDAP.

  OpenID [OpenID] is a decentralized single sign-on authentication
  system that allows users to log in at multiple web sites with one ID
  instead of having to create multiple unique accounts.  An end user
  can freely choose which OpenID provider to use and can preserve their
  Identifier if they switch OpenID providers.

  Note that OAuth and OpenID do not consistently require data
  confidentiality services to protect interactions between providers
  and consumers.  HTTP over TLS [RFC2818] can be used as needed to
  provide protection against man-in-the-middle attacks.

  SAML 2.0 [SAML] is an XML-based protocol that can be used to
  implement web-based authentication and authorization services,
  including single sign on.  It uses security tokens containing
  assertions to exchange information about an end user between an
  identity provider and a service provider.

  The Transport Layer Security protocol describes the specification of
  a client certificate in Section 7.4.6 of [RFC5246].  Clients who
  possess and present a valid X.509 digital certificate, issued by a
  CA, could be identified and authenticated by a server who trusts the
  corresponding CA.  A certificate authentication method can be used to
  achieve federated authentication in which multiple RDAP servers all
  trust the same CAs, and then any client with a certificate issued by
  a trusted CA can access any RDAP server in the federation.  This



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  certificate-based mechanism is supported by HTTPS and can be used
  with RDAP.

3.3.  Authorization

  WHOIS does not provide services to grant different levels of access
  to clients based on a client's authenticated identity.  As noted in
  Section 3.1.4.2 of "Cross Registry Internet Service Protocol (CRISP)
  Requirements" [RFC3707], there is utility in allowing server
  operators to offer "varying degrees of access depending on policy and
  need."  Access control decisions can be made once a client's identity
  has been established and authenticated (see Section 3.2).

  Server operators MAY offer varying degrees of access depending on
  policy and need in conjunction with the authentication methods
  described in Section 3.2.  If such varying degrees of access are
  supported, an RDAP server MUST provide granular access controls (that
  is, per registration data object) in order to implement authorization
  policies.  Some examples:

  -  Clients will be allowed access only to data for which they have a
     relationship.

  -  Unauthenticated or anonymous access status may not yield any
     contact information.

  -  Full access may be granted to a special group of authenticated
     clients.

  The type of access allowed by a server will most likely vary from one
  operator to the next.  A description of the response privacy
  considerations associated with different levels of authorization can
  be found in Section 13 of [RFC7483].

3.4.  Availability

  An RDAP service has to be available to be useful.  There are no RDAP-
  unique requirements to provide availability, but as a general
  security consideration, a service operator needs to be aware of the
  issues associated with denial of service.  A thorough reading of
  "Internet Denial-of-Service Considerations" [RFC4732] is advised.

  An RDAP service MAY use an HTTP throttling mechanism to limit the
  number of queries that a single client can send in a given period of
  time.  If used, the server SHOULD return an HTTP 429 (Too Many
  Requests) response code as described in "Additional HTTP Status
  Codes" [RFC6585].  A client that receives a 429 response SHOULD
  decrease its query rate and honor the Retry-After header field if one



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  is present.  Note that this is not a defense against
  denial-of-service attacks, since a malicious client could ignore the
  code and continue to send queries at a high rate.  A server might use
  another response code if it did not wish to reveal to a client that
  rate limiting is the reason for the denial of a reply.

3.5.  Data Confidentiality

  WHOIS does not provide the ability to protect data from inadvertent
  disclosure while in transit.  RDAP uses HTTP over TLS [RFC2818] to
  provide that protection by encrypting all traffic sent on the
  connection between client and server.  HTTP over TLS MUST be used to
  protect all client-server exchanges unless operational constraints
  make it impossible to meet this requirement.  It is also possible to
  encrypt discrete objects (such as command path segments and JSON-
  encoded response objects) at one endpoint, send them to the other
  endpoint via an unprotected transport protocol, and decrypt the
  object on receipt.  Encryption algorithms as described in "Internet
  Security Glossary, Version 2" [RFC4949] are commonly used to provide
  data confidentiality at the object level.

  There are no current requirements for object-level data
  confidentiality using encryption.  Support for this feature could be
  added to RDAP in the future.

  As noted in Section 3.2, the HTTP "basic" authentication scheme can
  be used to authenticate a client.  When this scheme is used, HTTP
  over TLS MUST be used to protect the client's credentials from
  disclosure while in transit.  If the policy of the server operator
  requires encryption to protect client-server data exchanges (such as
  to protect non-public data that cannot be accessed without client
  identification and authentication), HTTP over TLS MUST be used to
  protect those exchanges.

  A description of privacy threats that can be addressed with
  confidentiality services can be found in Section 4.  Section 10.2.2
  of [RFC7483] describes status values that can be used to describe
  operator actions used to protect response data from disclosure to
  unauthorized clients.

3.6.  Data Integrity

  WHOIS does not provide the ability to protect data from modification
  while in transit.  Web services such as RDAP commonly use HTTP over
  TLS [RFC2818] to provide that protection by using a keyed Message
  Authentication Code (MAC) to detect modifications.  It is also
  possible to sign discrete objects (such as command path segments and
  JSON-encoded response objects) at one endpoint, send them to the



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  other endpoint via a transport protocol, and validate the signature
  of the object on receipt.  Digital signature algorithms as described
  in "Internet Security Glossary, Version 2" [RFC4949] are commonly
  used to provide data integrity at the object level.

  There are no current requirements for object-level data integrity
  using digital signatures.  Support for this feature could be added to
  RDAP in the future.

  The most specific need for this service is to provide assurance that
  HTTP 30x redirection hints [RFC7231] and response elements returned
  from the server are not modified while in transit.  If the policy of
  the server operator requires message integrity for client-server data
  exchanges, HTTP over TLS MUST be used to protect those exchanges.

4.  Privacy Threats Associated with Registration Data

  Registration data has historically included personal data about
  registrants.  WHOIS services have historically made this information
  available to the public, creating a privacy risk by revealing the
  personal details of registrants.  WHOIS services have not had the
  benefit of authentication or access control mechanisms to gate access
  to registration data.  As a result of this, proxy and privacy
  services have arisen to shield the identities of registrants.

  The standardization of RDAP does not change or impact the data that
  operators may require to be collected from registrants, but it
  provides support for a number of mechanisms that may be used to
  mitigate privacy threats to registrants should operators choose to
  use them.

  RDAP includes mechanisms that can be used to authenticate clients,
  allowing servers to support tiered access based on local policy.
  This means that all registration data need no longer be public, and
  personal data or data that may be considered more sensitive can have
  its access restricted to specifically privileged clients.

  RDAP data structures allow servers to indicate via status values when
  data returned to clients has been made private, redacted, obscured,
  or registered by a proxy.  "Private" means that the data is not
  designated for public consumption.  "Redacted" means that some
  registration data fields are not being made available.  "Obscured"
  means that data has been altered for the purposes of not readily
  revealing the actual registration information.  One option that
  operators have available to them to reduce privacy risks to
  registrants is to adopt policies that make use of these status values
  to restrict the registrant data shared with any or all clients




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  according to the sensitivity of the data, the privileges of the
  clients, or some other heuristics.

  RDAP uses the jCard [RFC7095] standard format for entity
  representation.  Operators may find that many of the jCard fields are
  irrelevant for registry operation purposes or that they have no
  reason to collect information from registrants that would correspond
  to certain fields.  Operators wishing to reduce privacy risks for
  registrants may restrict which information they collect and/or which
  fields they populate in responses.

  In addition to privacy risks to registrants, there are also potential
  privacy risks for those who query registration data.  For example,
  the fact that a registry employee performs a particular query may
  reveal information about the employee's activities that he or she
  would have preferred to keep private.  RDAP supports the use of HTTP
  over TLS to provide privacy protection for those querying registrant
  data as well as registrants, unless operational constraints make it
  impossible to meet this requirement.

5.  Security Considerations

  One of the goals of RDAP is to provide security services that do not
  exist in the WHOIS protocol.  This document describes the security
  services provided by RDAP and associated protocol layers, including
  authentication, authorization, availability, data confidentiality,
  and data integrity.  Non-repudiation services were also considered
  and ultimately rejected due to a lack of requirements.  There are,
  however, currently deployed WHOIS servers that can return signed
  responses that provide non-repudiation with proof of origin.  RDAP
  might need to be extended to provide this service in the future.

  As an HTTP-based protocol, RDAP is susceptible to code injection
  attacks.  Code injection refers to adding code into a computer system
  or program to alter the course of execution.  There are many types of
  code injection, including SQL injection, dynamic variable or function
  injection, include-file injection, shell injection, and HTML-script
  injection, among others.  Data confidentiality and integrity services
  provide a measure of defense against man-in-the-middle injection
  attacks, but vulnerabilities in both client- and server-side software
  make it possible for injection attacks to succeed.  Consistently
  checking and validating server credentials can help detect
  man-in-the-middle attacks.

  As noted in Section 3.2.1, digital certificates can be used to
  implement federated authentication.  There is a risk of too
  promiscuous, or even rogue, CAs being included in the list of
  acceptable CAs that the TLS server sends the client as part of the



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  TLS client-authentication handshake and lending the appearance of
  trust to certificates signed by those CAs.  Periodic monitoring of
  the list of CAs that RDAP servers trust for client authentication can
  help reduce this risk.

  The Transport Layer Security protocol [RFC5246] includes a null
  cipher suite that does not encrypt data and thus does not provide
  data confidentiality.  This option MUST NOT be used when data
  confidentiality services are needed.  Additional considerations for
  secure use of TLS are described in [SECURE-TLS-DTLS].

  Data integrity services are sometimes mistakenly associated with
  directory service operational policy requirements focused on data
  accuracy.  "Accuracy" refers to the truthful association of data
  elements (such as names, addresses, and telephone numbers) in the
  context of a particular directory object (such as a domain name).
  Accuracy requirements are out of scope for this protocol.

  Additional security considerations are described in the
  specifications for HTTP [RFC7231], HTTP Basic and Digest access
  authentication [RFC7235], HTTP over TLS [RFC2818], and additional
  HTTP status codes [RFC6585].  Security considerations for federated
  authentication systems can be found in the OAuth [RFC6749] and OpenID
  [OpenID] specifications.

6.  References

6.1.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997,
             <http://www.rfc-editor.org/info/rfc2119>.

  [RFC2818]  Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000,
             <http://www.rfc-editor.org/info/rfc2818>.

  [RFC6585]  Nottingham, M. and R. Fielding, "Additional HTTP Status
             Codes", RFC 6585, April 2012,
             <http://www.rfc-editor.org/info/rfc6585>.

  [RFC7231]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
             Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
             June 2014, <http://www.rfc-editor.org/info/rfc7231>.

  [RFC7235]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
             Protocol (HTTP/1.1): Authentication", RFC 7235, June 2014,
             <http://www.rfc-editor.org/info/rfc7235>.




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  [RFC7480]  Newton, A., Ellacott, B., and N. Kong, "HTTP Usage in the
             Registration Data Access Protocol (RDAP)", RFC 7480, March
             2015, <http://www.rfc-editor.org/info/rfc7480>.

  [RFC7482]  Newton, A. and S. Hollenbeck, "Registration Data Access
             Protocol (RDAP) Query Format", RFC 7482, March 2015,
             <http://www.rfc-editor.org/info/rfc7482>.

  [RFC7483]  Newton, A. and S. Hollenbeck, "JSON Responses for the
             Registration Data Access Protocol (RDAP)", RFC 7483, March
             2015, <http://www.rfc-editor.org/info/rfc7483>.

6.2.  Informative References

  [OpenID]   OpenID Foundation, "OpenID Authentication 2.0 - Final",
             December 2007, <http://specs.openid.net/auth/2.0>.

  [RFC3707]  Newton, A., "Cross Registry Internet Service Protocol
             (CRISP) Requirements", RFC 3707, February 2004,
             <http://www.rfc-editor.org/info/rfc3707>.

  [RFC3912]  Daigle, L., "WHOIS Protocol Specification", RFC 3912,
             September 2004, <http://www.rfc-editor.org/info/rfc3912>.

  [RFC4732]  Handley, M., Ed., Rescorla, E., Ed., and IAB, "Internet
             Denial-of-Service Considerations", RFC 4732, December
             2006, <http://www.rfc-editor.org/info/rfc4732>.

  [RFC4949]  Shirey, R., "Internet Security Glossary, Version 2", FYI
             36, RFC 4949, August 2007,
             <http://www.rfc-editor.org/info/rfc4949>.

  [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
             (TLS) Protocol Version 1.2", RFC 5246, August 2008,
             <http://www.rfc-editor.org/info/rfc5246>.

  [RFC5280]  Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
             Housley, R., and W. Polk, "Internet X.509 Public Key
             Infrastructure Certificate and Certificate Revocation List
             (CRL) Profile", RFC 5280, May 2008,
             <http://www.rfc-editor.org/info/rfc5280>.

  [RFC6749]  Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
             RFC 6749, October 2012,
             <http://www.rfc-editor.org/info/rfc6749>.

  [RFC7095]  Kewisch, P., "jCard: The JSON Format for vCard", RFC 7095,
             January 2014, <http://www.rfc-editor.org/info/rfc7095>.



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  [SAML]     OASIS, "Security Assertion Markup Language (SAML) v2.0",
             March 2005, <https://www.oasis-open.org/
             standards#samlv2.0>.

  [SECURE-TLS-DTLS]
             Sheffer, Y., Holz, R., and P. Saint-Andre,
             "Recommendations for Secure Use of TLS and DTLS", Work in
             Progress, draft-ietf-uta-tls-bcp-09, February 2015.











































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Acknowledgements

  The authors would like to acknowledge the following individuals for
  their contributions to this document: Richard Barnes, Marc Blanchet,
  Alissa Cooper, Ernie Dainow, Spencer Dawkins, Jean-Philippe Dionne,
  Byron Ellacott, Stephen Farrell, Tony Hansen, Peter Koch, Murray
  Kucherawy, Barry Leiba, Andrew Newton, and Linlin Zhou.

Authors' Addresses

  Scott Hollenbeck
  Verisign Labs
  12061 Bluemont Way
  Reston, VA  20190
  United States

  EMail: [email protected]
  URI:   http://www.verisignlabs.com/


  Ning Kong
  China Internet Network Information Center
  4 South 4th Street, Zhongguancun, Haidian District
  Beijing  100190
  China

  Phone: +86 10 5881 3147
  EMail: [email protected]























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=========================================================================



Internet Engineering Task Force (IETF)                     S. Hollenbeck
Request for Comments: 9082                                 Verisign Labs
STD: 95                                                        A. Newton
Obsoletes: 7482                                                      AWS
Category: Standards Track                                      June 2021
ISSN: 2070-1721


        Registration Data Access Protocol (RDAP) Query Format

Abstract

  This document describes uniform patterns to construct HTTP URLs that
  may be used to retrieve registration information from registries
  (including both Regional Internet Registries (RIRs) and Domain Name
  Registries (DNRs)) using "RESTful" web access patterns.  These
  uniform patterns define the query syntax for the Registration Data
  Access Protocol (RDAP).  This document obsoletes RFC 7482.

Status of This Memo

  This is an Internet Standards Track document.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Further information on
  Internet Standards is available in Section 2 of RFC 7841.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  https://www.rfc-editor.org/info/rfc9082.

Copyright Notice

  Copyright (c) 2021 IETF Trust and the persons identified as the
  document authors.  All rights reserved.

  This document is subject to BCP 78 and the IETF Trust's Legal
  Provisions Relating to IETF Documents
  (https://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.

Table of Contents

  1.  Introduction
  2.  Conventions Used in This Document
    2.1.  Acronyms and Abbreviations
  3.  Path Segment Specification
    3.1.  Lookup Path Segment Specification
      3.1.1.  IP Network Path Segment Specification
      3.1.2.  Autonomous System Path Segment Specification
      3.1.3.  Domain Path Segment Specification
      3.1.4.  Nameserver Path Segment Specification
      3.1.5.  Entity Path Segment Specification
      3.1.6.  Help Path Segment Specification
    3.2.  Search Path Segment Specification
      3.2.1.  Domain Search
      3.2.2.  Nameserver Search
      3.2.3.  Entity Search
  4.  Query Processing
    4.1.  Partial String Searching
    4.2.  Associated Records
  5.  Extensibility
  6.  Internationalization Considerations
    6.1.  Character Encoding Considerations
  7.  IANA Considerations
  8.  Security Considerations
  9.  References
    9.1.  Normative References
    9.2.  Informative References
  Appendix A.  Changes from RFC 7482
  Acknowledgments
  Authors' Addresses

1.  Introduction

  This document describes a specification for querying registration
  data using a RESTful web service and uniform query patterns.  The
  service is implemented using the Hypertext Transfer Protocol (HTTP)
  [RFC7230] and the conventions described in [RFC7480].  These uniform
  patterns define the query syntax for the Registration Data Access
  Protocol (RDAP).  This document obsoletes RFC 7482.

  The protocol described in this specification is intended to address
  deficiencies with the WHOIS protocol [RFC3912] that have been
  identified over time, including:

  *  lack of standardized command structures;

  *  lack of standardized output and error structures;

  *  lack of support for internationalization and localization; and

  *  lack of support for user identification, authentication, and
     access control.

  The patterns described in this document purposefully do not encompass
  all of the methods employed in the WHOIS and other RESTful web
  services used by the RIRs and DNRs.  The intent of the patterns
  described here is to enable queries of:

  *  networks by IP address;

  *  Autonomous System (AS) numbers by number;

  *  reverse DNS metadata by domain;

  *  nameservers by name; and

  *  entities (such as registrars and contacts) by identifier.

  Server implementations are free to support only a subset of these
  features depending on local requirements.  Servers MUST return an
  HTTP 501 (Not Implemented) [RFC7231] response to inform clients of
  unsupported query types.  It is also envisioned that each registry
  will continue to maintain WHOIS and/or other RESTful web services
  specific to their needs and those of their constituencies, and the
  information retrieved through the patterns described here may
  reference such services.

  Likewise, future IETF specifications may add additional patterns for
  additional query types.  A simple pattern namespacing scheme is
  described in Section 5 to accommodate custom extensions that will not
  interfere with the patterns defined in this document or patterns
  defined in future IETF specifications.

  WHOIS services, in general, are read-only services.  Accordingly, URL
  [RFC3986] patterns specified in this document are only applicable to
  the HTTP [RFC7231] GET and HEAD methods.

  This document does not describe the results or entities returned from
  issuing the described URLs with an HTTP GET.  The specification of
  these entities is described in [RFC9083].

  Additionally, resource management, provisioning, and update functions
  are out of scope for this document.  Registries have various and
  divergent methods covering these functions, and it is unlikely a
  uniform approach is needed for interoperability.

  HTTP contains mechanisms for servers to authenticate clients and for
  clients to authenticate servers (from which authorization schemes may
  be built), so such mechanisms are not described in this document.
  Policy, provisioning, and processing of authentication and
  authorization are out of scope for this document as deployments will
  have to make choices based on local criteria.  Supported
  authentication mechanisms are described in [RFC7481].

2.  Conventions Used in This Document

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
  "OPTIONAL" in this document are to be interpreted as described in
  BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
  capitals, as shown here.

2.1.  Acronyms and Abbreviations

  IDN:  Internationalized Domain Name, a fully-qualified domain name
     containing one or more labels that are intended to include one or
     more Unicode code points outside the ASCII range (cf. "domain
     name", "fully-qualified domain name", and "internationalized
     domain name" in RFC 8499 [RFC8499]).

  IDNA:  Internationalized Domain Names in Applications, a protocol for
     the handling of IDNs.  In this document, "IDNA" refers
     specifically to the version of those specifications known as
     "IDNA2008" [RFC5890].

  DNR:  Domain Name Registry or Domain Name Registrar

  NFC:  Unicode Normalization Form C [Unicode-UAX15]

  NFKC:  Unicode Normalization Form KC [Unicode-UAX15]

  RDAP:  Registration Data Access Protocol

  REST:  Representational State Transfer.  The term was first described
     in a doctoral dissertation [REST].

  RESTful:  An adjective that describes a service using HTTP and the
     principles of REST.

  RIR:  Regional Internet Registry

3.  Path Segment Specification

  The base URLs used to construct RDAP queries are maintained in an
  IANA registry (the "bootstrap registry") described in [RFC7484].
  Queries are formed by retrieving an appropriate base URL from the
  registry and appending a path segment specified in either Sections
  3.1 or 3.2.  Generally, a registry or other service provider will
  provide a base URL that identifies the protocol, host, and port, and
  this will be used as a base URL that the complete URL is resolved
  against, as per Section 5 of RFC 3986 [RFC3986].  For example, if the
  base URL is "https://example.com/rdap/", all RDAP query URLs will
  begin with "https://example.com/rdap/".

  The bootstrap registry does not contain information for query objects
  that are not part of a global namespace, including entities and help.
  A base URL for an associated object is required to construct a
  complete query.  This limitation can be overcome for entities by
  using the practice described in RFC 8521 [RFC8521].

  For entities, a base URL is retrieved for the service (domain,
  address, etc.) associated with a given entity.  The query URL is
  constructed by concatenating the base URL with the entity path
  segment specified in either Sections 3.1.5 or 3.2.3.

  For help, a base URL is retrieved for any service (domain, address,
  etc.) for which additional information is required.  The query URL is
  constructed by concatenating the base URL with the help path segment
  specified in Section 3.1.6.

3.1.  Lookup Path Segment Specification

  A simple lookup to determine if an object exists (or not) without
  returning RDAP-encoded results can be performed using the HTTP HEAD
  method as described in Section 4.1 of [RFC7480].

  The resource type path segments for exact match lookup are:

  'ip':  Used to identify IP networks and associated data referenced
     using either an IPv4 or IPv6 address.

  'autnum':  Used to identify Autonomous System number registrations
     and associated data referenced using an asplain Autonomous System
     number.

  'domain':  Used to identify reverse DNS (RIR) or domain name (DNR)
     information and associated data referenced using a fully qualified
     domain name.

  'nameserver':  Used to identify a nameserver information query using
     a host name.

  'entity':  Used to identify an entity information query using a
     string identifier.

3.1.1.  IP Network Path Segment Specification

  Syntax:  ip/<IP address> or ip/<CIDR prefix>/<CIDR length>

  Queries for information about IP networks are of the form /ip/XXX or
  /ip/XXX/YY where the path segment following 'ip' is either an IPv4
  dotted decimal or IPv6 [RFC5952] address (i.e., XXX) or an IPv4 or
  IPv6 Classless Inter-domain Routing (CIDR) [RFC4632] notation address
  block (i.e., XXX/YY).  Semantically, the simpler form using the
  address can be thought of as a CIDR block with a prefix length of 32
  for IPv4 and a prefix length of 128 for IPv6.  A given specific
  address or CIDR may fall within multiple IP networks in a hierarchy
  of networks; therefore, this query targets the "most-specific" or
  smallest IP network that completely encompasses it in a hierarchy of
  IP networks.

  The IPv4 and IPv6 address formats supported in this query are
  described in Section 3.2.2 of RFC 3986 [RFC3986] as IPv4address and
  IPv6address ABNF definitions.  Any valid IPv6 text address format
  [RFC4291] can be used.  This includes IPv6 addresses written using
  with or without compressed zeros and IPv6 addresses containing
  embedded IPv4 addresses.  The rules to write a text representation of
  an IPv6 address [RFC5952] are RECOMMENDED.  However, the zone_id
  [RFC4007] is not appropriate in this context; therefore, the
  corresponding syntax extension in RFC 6874 [RFC6874] MUST NOT be
  used, and servers SHOULD ignore it.

  For example, the following URL would be used to find information for
  the most specific network containing 192.0.2.0:

  https://example.com/rdap/ip/192.0.2.0

  The following URL would be used to find information for the most
  specific network containing 192.0.2.0/24:

  https://example.com/rdap/ip/192.0.2.0/24

  The following URL would be used to find information for the most
  specific network containing 2001:db8::

  https://example.com/rdap/ip/2001:db8::

3.1.2.  Autonomous System Path Segment Specification

  Syntax:  autnum/<autonomous system number>

  Queries for information regarding Autonomous System number
  registrations are of the form /autnum/XXX where XXX is an asplain
  Autonomous System number [RFC5396].  In some registries, registration
  of Autonomous System numbers is done on an individual number basis,
  while other registries may register blocks of Autonomous System
  numbers.  The semantics of this query are such that if a number falls
  within a range of registered blocks, the target of the query is the
  block registration and that individual number registrations are
  considered a block of numbers with a size of 1.

  For example, the following URL would be used to find information
  describing Autonomous System number 12 (a number within a range of
  registered blocks):

  https://example.com/rdap/autnum/12

  The following URL would be used to find information describing 4-byte
  Autonomous System number 65538:

  https://example.com/rdap/autnum/65538

3.1.3.  Domain Path Segment Specification

  Syntax:  domain/<domain name>

  Queries for domain information are of the form /domain/XXXX, where
  XXXX is a fully qualified (relative to the root) domain name (as
  specified in [RFC0952] and [RFC1123]) in either the in-addr.arpa or
  ip6.arpa zones (for RIRs) or a fully qualified domain name in a zone
  administered by the server operator (for DNRs).  Internationalized
  Domain Names (IDNs) represented in either A-label or U-label format
  [RFC5890] are also valid domain names.  See Section 6.1 for
  information on character encoding for the U-label format.

  IDNs SHOULD NOT be represented as a mixture of A-labels and U-labels;
  that is, internationalized labels in an IDN SHOULD be either all
  A-labels or all U-labels.  It is possible for an RDAP client to
  assemble a query string from multiple independent data sources.  Such
  a client might not be able to perform conversions between A-labels
  and U-labels.  An RDAP server that receives a query string with a
  mixture of A-labels and U-labels MAY convert all the U-labels to
  A-labels, perform IDNA processing, and proceed with exact-match
  lookup.  In such cases, the response to be returned to the query
  source may not match the input from the query source.  Alternatively,
  the server MAY refuse to process the query.

  The server MAY perform the match using either the A-label or U-label
  form.  Using one consistent form for matching every label is likely
  to be more reliable.

  The following URL would be used to find information describing the
  zone serving the network 192.0.2/24:

  https://example.com/rdap/domain/2.0.192.in-addr.arpa

  The following URL would be used to find information describing the
  zone serving the network 2001:db8:1::/48:

  https://example.com/rdap/domain/1.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa

  The following URL would be used to find information for the
  blah.example.com domain name:

  https://example.com/rdap/domain/blah.example.com

  The following URL would be used to find information for the
  xn--fo-5ja.example IDN:

  https://example.com/rdap/domain/xn--fo-5ja.example

3.1.4.  Nameserver Path Segment Specification

  Syntax:  nameserver/<nameserver name>

  The <nameserver name> parameter represents a fully qualified host
  name as specified in [RFC0952] and [RFC1123].  Internationalized
  names represented in either A-label or U-label format [RFC5890] are
  also valid nameserver names.  IDN processing for nameserver names
  uses the domain name processing instructions specified in
  Section 3.1.3.  See Section 6.1 for information on character encoding
  for the U-label format.

  The following URL would be used to find information for the
  ns1.example.com nameserver:

  https://example.com/rdap/nameserver/ns1.example.com

  The following URL would be used to find information for the
  ns1.xn--fo-5ja.example nameserver:

  https://example.com/rdap/nameserver/ns1.xn--fo-5ja.example

3.1.5.  Entity Path Segment Specification

  Syntax:  entity/<handle>

  The <handle> parameter represents an entity (such as a contact,
  registrant, or registrar) identifier whose syntax is specific to the
  registration provider.  For example, for some DNRs, contact
  identifiers are specified in [RFC5730] and [RFC5733].

  The following URL would be used to find information for the entity
  associated with handle XXXX:

  https://example.com/rdap/entity/XXXX

3.1.6.  Help Path Segment Specification

  Syntax:  help

  The help path segment can be used to request helpful information
  (command syntax, terms of service, privacy policy, rate-limiting
  policy, supported authentication methods, supported extensions,
  technical support contact, etc.) from an RDAP server.  The response
  to "help" should provide basic information that a client needs to
  successfully use the service.  The following URL would be used to
  return "help" information:

  https://example.com/rdap/help

3.2.  Search Path Segment Specification

  Pattern matching semantics are described in Section 4.1.  The
  resource type path segments for search are:

  'domains':  Used to identify a domain name information search using a
     pattern to match a fully qualified domain name.

  'nameservers':  Used to identify a nameserver information search
     using a pattern to match a host name.

  'entities':  Used to identify an entity information search using a
     pattern to match a string identifier.

  RDAP search path segments are formed using a concatenation of the
  plural form of the object being searched for and an HTTP query
  string.  The HTTP query string is formed using a concatenation of the
  question mark character ('?', US-ASCII value 0x003F), a noun
  representing the JSON object property associated with the object
  being searched for, the equal sign character ('=', US-ASCII value
  0x003D), and the search pattern (this is in contrast to the more
  generic HTTP query string that allows multiple simultaneous
  parameters).  Search pattern query processing is described more fully
  in Section 4.  For the domain, nameserver, and entity objects
  described in this document, the plural object forms are "domains",
  "nameservers", and "entities".

  Detailed results can be retrieved using the HTTP GET method and the
  path segments specified here.

3.2.1.  Domain Search

  Syntax:  domains?name=<domain search pattern>

  Syntax:  domains?nsLdhName=<nameserver search pattern>

  Syntax:  domains?nsIp=<nameserver IP address>

  Searches for domain information by name are specified using this
  form:

  domains?name=XXXX

  XXXX is a search pattern representing a domain name in "letters,
  digits, hyphen" (LDH) format [RFC5890].  The following URL would be
  used to find DNR information for domain names matching the
  "example*.com" pattern:

  https://example.com/rdap/domains?name=example*.com

  IDNs in U-label format [RFC5890] can also be used as search patterns
  (see Section 4).  Searches for these names are of the form
  /domains?name=XXXX, where XXXX is a search pattern representing a
  domain name in U-label format [RFC5890].  See Section 6.1 for
  information on character encoding for the U-label format.

  Searches for domain information by nameserver name are specified
  using this form:

  domains?nsLdhName=YYYY

  YYYY is a search pattern representing a host name in "letters,
  digits, hyphen" format [RFC5890].  The following URL would be used to
  search for domains delegated to nameservers matching the
  "ns1.example*.com" pattern:

  https://example.com/rdap/domains?nsLdhName=ns1.example*.com

  Searches for domain information by nameserver IP address are
  specified using this form:

  domains?nsIp=ZZZZ

  ZZZZ is an IPv4 [RFC1166] or IPv6 [RFC5952] address.  The following
  URL would be used to search for domains that have been delegated to
  nameservers that resolve to the "192.0.2.0" address:

  https://example.com/rdap/domains?nsIp=192.0.2.0

3.2.2.  Nameserver Search

  Syntax:  nameservers?name=<nameserver search pattern>

  Syntax:  nameservers?ip=<nameserver IP address>

  Searches for nameserver information by nameserver name are specified
  using this form:

  nameservers?name=XXXX

  XXXX is a search pattern representing a host name in "letters,
  digits, hyphen" format [RFC5890].  The following URL would be used to
  find information for nameserver names matching the "ns1.example*.com"
  pattern:

  https://example.com/rdap/nameservers?name=ns1.example*.com

  Internationalized nameserver names in U-label format [RFC5890] can
  also be used as search patterns (see Section 4).  Searches for these
  names are of the form /nameservers?name=XXXX, where XXXX is a search
  pattern representing a nameserver name in U-label format [RFC5890].
  See Section 6.1 for information on character encoding for the U-label
  format.

  Searches for nameserver information by nameserver IP address are
  specified using this form:

  nameservers?ip=YYYY

  YYYY is an IPv4 [RFC1166] or IPv6 [RFC5952] address.  The following
  URL would be used to search for nameserver names that resolve to the
  "192.0.2.0" address:

  https://example.com/rdap/nameservers?ip=192.0.2.0

3.2.3.  Entity Search

  Syntax:  entities?fn=<entity name search pattern>

  Syntax:  entities?handle=<entity handle search pattern>

  Searches for entity information by name are specified using this
  form:

  entities?fn=XXXX

  XXXX is a search pattern representing the "fn" property of an entity
  (such as a contact, registrant, or registrar) name as described in
  Section 5.1 of [RFC9083].  The following URL would be used to find
  information for entity names matching the "Bobby Joe*" pattern:

  https://example.com/rdap/entities?fn=Bobby%20Joe*

  Searches for entity information by handle are specified using this
  form:

  entities?handle=XXXX

  XXXX is a search pattern representing an entity (such as a contact,
  registrant, or registrar) identifier whose syntax is specific to the
  registration provider.  The following URL would be used to find
  information for entity handles matching the "CID-40*" pattern:

  https://example.com/rdap/entities?handle=CID-40*

  URLs MUST be properly encoded according to the rules of [RFC3986].
  In the example above, "Bobby Joe*" is encoded to "Bobby%20Joe*".

4.  Query Processing

  Servers indicate the success or failure of query processing by
  returning an appropriate HTTP response code to the client.  Response
  codes not specifically identified in this document are described in
  [RFC7480].

4.1.  Partial String Searching

  Partial string searching uses the asterisk ('*', US-ASCII value 0x2A)
  character to match zero or more trailing characters.  A character
  string representing a domain label suffix MAY be concatenated to the
  end of the search pattern to limit the scope of the search.  For
  example, the search pattern "exam*" will match "example.com" and
  "example.net".  The search pattern "exam*.com" will match
  "example.com".  If an asterisk appears in a search string, any label
  that contains the non-asterisk characters in sequence plus zero or
  more characters in sequence in place of the asterisk would match.  A
  partial string search MUST NOT include more than one asterisk.
  Additional pattern matching processing is beyond the scope of this
  specification.

  If a server receives a search request but cannot process the request
  because it does not support a particular style of partial match
  searching, it SHOULD return an HTTP 422 (Unprocessable Entity)
  [RFC4918] response (unless another response code is more appropriate
  based on a server's policy settings) to note that search
  functionality is supported, but this particular query cannot be
  processed.  When returning a 422 error, the server MAY also return an
  error response body as specified in Section 6 of [RFC9083] if the
  requested media type is one that is specified in [RFC7480].

  Partial matching is not feasible across combinations of Unicode
  characters because Unicode characters can be combined with each
  other.  Servers SHOULD NOT partially match combinations of Unicode
  characters where a legal combination is possible.  It should be
  noted, though, that it may not always be possible to detect cases
  where a character could have been combined with another character,
  but was not, because characters can be combined in many different
  ways.

  Clients SHOULD NOT submit a partial match search of Unicode
  characters where a Unicode character may be legally combined with
  another Unicode character or characters.  Partial match searches with
  incomplete combinations of characters where a character must be
  combined with another character or characters are invalid.  Partial
  match searches with characters that may be combined with another
  character or characters are to be considered non-combined characters
  (that is, if character x may be combined with character y but
  character y is not submitted in the search string, then character x
  is a complete character and no combinations of character x are to be
  searched).

4.2.  Associated Records

  Conceptually, any query-matching record in a server's database might
  be a member of a set of related records, related in some fashion as
  defined by the server -- for example, variants of an IDN.  The entire
  set ought to be considered as candidates for inclusion when
  constructing the response.  However, the construction of the final
  response needs to be mindful of privacy and other data-releasing
  policies when assembling the RDAP response set.

  Note too that due to the nature of searching, there may be a list of
  query-matching records.  Each one of those is subject to being a
  member of a set as described in the previous paragraph.  What is
  ultimately returned in a response will be the union of all the sets
  that has been filtered by whatever policies are in place.

  Note that this model includes arrangements for associated names,
  including those that are linked by policy mechanisms and names bound
  together for some other purposes.  Note also that returning
  information that was not explicitly selected by an exact-match
  lookup, including additional names that match a relatively fuzzy
  search as well as lists of names that are linked together, may cause
  privacy issues.

  Note that there might not be a single, static information return
  policy that applies to all clients equally.  Client identity and
  associated authorizations can be a relevant factor in determining how
  broad the response set will be for any particular query.

5.  Extensibility

  This document describes path segment specifications for a limited
  number of objects commonly registered in both RIRs and DNRs.  It does
  not attempt to describe path segments for all of the objects
  registered in all registries.  Custom path segments can be created
  for objects not specified here using the process described in
  Section 6 of "HTTP Usage in the Registration Data Access Protocol
  (RDAP)" [RFC7480].

  Custom path segments can be created by prefixing the segment with a
  unique identifier followed by an underscore character (0x5F).  For
  example, a custom entity path segment could be created by prefixing
  "entity" with "custom_", producing "custom_entity".  Servers MUST
  return an appropriate failure status code for a request with an
  unrecognized path segment.

6.  Internationalization Considerations

  There is value in supporting the ability to submit either a U-label
  (Unicode form of an IDN label) or an A-label (US-ASCII form of an IDN
  label) as a query argument to an RDAP service.  Clients capable of
  processing non-US-ASCII characters may prefer a U-label since this is
  more visually recognizable and familiar than A-label strings, but
  clients using programmatic interfaces might find it easier to submit
  and display A-labels if they are unable to input U-labels with their
  keyboard configuration.  Both query forms are acceptable.

  Internationalized domain and nameserver names can contain character
  variants and variant labels as described in [RFC4290].  Clients that
  support queries for internationalized domain and nameserver names
  MUST accept service provider responses that describe variants as
  specified in "JSON Responses for the Registration Data Access
  Protocol (RDAP)" [RFC9083].

6.1.  Character Encoding Considerations

  Servers can expect to receive search patterns from clients that
  contain character strings encoded in different forms supported by
  HTTP.  It is entirely possible to apply filters and normalization
  rules to search patterns prior to making character comparisons, but
  this type of processing is more typically needed to determine the
  validity of registered strings than to match patterns.

  An RDAP client submitting a query string containing non-US-ASCII
  characters converts such strings into Unicode in UTF-8 encoding.  It
  then performs any local case mapping deemed necessary.  Strings are
  normalized using Normalization Form C (NFC) [Unicode-UAX15]; note
  that clients might not be able to do this reliably.  UTF-8 encoded
  strings are then appropriately percent-encoded [RFC3986] in the query
  URL.

  After parsing any percent-encoding, an RDAP server treats each query
  string as Unicode in UTF-8 encoding.  If a string is not valid UTF-8,
  the server can immediately stop processing the query and return an
  HTTP 400 (Bad Request) response.

  When processing queries, there is a difference in handling DNS names,
  including those with putative U-labels, and everything else.  DNS
  names are treated according to the DNS matching rules as described in
  Section 3.1 of RFC 1035 [RFC1035] for Non-Reserved LDH (NR-LDH)
  labels and the matching rules described in Section 5.4 of RFC 5891
  [RFC5891] for U-labels.  Matching of DNS names proceeds one label at
  a time because it is possible for a combination of U-labels and NR-
  LDH labels to be found in a single domain or host name.  The
  determination of whether a label is a U-label or an NR-LDH label is
  based on whether the label contains any characters outside of the US-
  ASCII letters, digits, or hyphen (the so-called LDH rule).

  For everything else, servers map fullwidth and halfwidth characters
  to their decomposition equivalents.  Servers convert strings to the
  same coded character set of the target data that is to be looked up
  or searched, and each string is normalized using the same
  normalization that was used on the target data.  In general, storage
  of strings as Unicode is RECOMMENDED.  For the purposes of
  comparison, Normalization Form KC (NFKC) [Unicode-UAX15] with case
  folding is used to maximize predictability and the number of matches.
  Note the use of case-folded NFKC as opposed to NFC in this case.

7.  IANA Considerations

  This document has no IANA actions.

8.  Security Considerations

  Security services for the operations specified in this document are
  described in "Security Services for the Registration Data Access
  Protocol (RDAP)" [RFC7481].

  Search functionality typically requires more server resources (such
  as memory, CPU cycles, and network bandwidth) when compared to basic
  lookup functionality.  This increases the risk of server resource
  exhaustion and subsequent denial of service due to abuse.  This risk
  can be mitigated by developing and implementing controls to restrict
  search functionality to identified and authorized clients.  If those
  clients behave badly, their search privileges can be suspended or
  revoked.  Rate limiting as described in Section 5.5 of "HTTP Usage in
  the Registration Data Access Protocol (RDAP)" [RFC7480] can also be
  used to control the rate of received search requests.  Server
  operators can also reduce their risk by restricting the amount of
  information returned in response to a search request.

  Search functionality also increases the privacy risk of disclosing
  object relationships that might not otherwise be obvious.  For
  example, a search that returns IDN variants [RFC6927] that do not
  explicitly match a client-provided search pattern can disclose
  information about registered domain names that might not be otherwise
  available.  Implementers need to consider the policy and privacy
  implications of returning information that was not explicitly
  requested.

  Note that there might not be a single, static information return
  policy that applies to all clients equally.  Client identity and
  associated authorizations can be a relevant factor in determining how
  broad the response set will be for any particular query.

9.  References

9.1.  Normative References

  [RFC0952]  Harrenstien, K., Stahl, M., and E. Feinler, "DoD Internet
             host table specification", RFC 952, DOI 10.17487/RFC0952,
             October 1985, <https://www.rfc-editor.org/info/rfc952>.

  [RFC1035]  Mockapetris, P., "Domain names - implementation and
             specification", STD 13, RFC 1035, DOI 10.17487/RFC1035,
             November 1987, <https://www.rfc-editor.org/info/rfc1035>.

  [RFC1123]  Braden, R., Ed., "Requirements for Internet Hosts -
             Application and Support", STD 3, RFC 1123,
             DOI 10.17487/RFC1123, October 1989,
             <https://www.rfc-editor.org/info/rfc1123>.

  [RFC1166]  Kirkpatrick, S., Stahl, M., and M. Recker, "Internet
             numbers", RFC 1166, DOI 10.17487/RFC1166, July 1990,
             <https://www.rfc-editor.org/info/rfc1166>.

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119,
             DOI 10.17487/RFC2119, March 1997,
             <https://www.rfc-editor.org/info/rfc2119>.

  [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
             Resource Identifier (URI): Generic Syntax", STD 66,
             RFC 3986, DOI 10.17487/RFC3986, January 2005,
             <https://www.rfc-editor.org/info/rfc3986>.

  [RFC4291]  Hinden, R. and S. Deering, "IP Version 6 Addressing
             Architecture", RFC 4291, DOI 10.17487/RFC4291, February
             2006, <https://www.rfc-editor.org/info/rfc4291>.

  [RFC4632]  Fuller, V. and T. Li, "Classless Inter-domain Routing
             (CIDR): The Internet Address Assignment and Aggregation
             Plan", BCP 122, RFC 4632, DOI 10.17487/RFC4632, August
             2006, <https://www.rfc-editor.org/info/rfc4632>.

  [RFC4918]  Dusseault, L., Ed., "HTTP Extensions for Web Distributed
             Authoring and Versioning (WebDAV)", RFC 4918,
             DOI 10.17487/RFC4918, June 2007,
             <https://www.rfc-editor.org/info/rfc4918>.

  [RFC5396]  Huston, G. and G. Michaelson, "Textual Representation of
             Autonomous System (AS) Numbers", RFC 5396,
             DOI 10.17487/RFC5396, December 2008,
             <https://www.rfc-editor.org/info/rfc5396>.

  [RFC5730]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
             STD 69, RFC 5730, DOI 10.17487/RFC5730, August 2009,
             <https://www.rfc-editor.org/info/rfc5730>.

  [RFC5733]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)
             Contact Mapping", STD 69, RFC 5733, DOI 10.17487/RFC5733,
             August 2009, <https://www.rfc-editor.org/info/rfc5733>.

  [RFC5890]  Klensin, J., "Internationalized Domain Names for
             Applications (IDNA): Definitions and Document Framework",
             RFC 5890, DOI 10.17487/RFC5890, August 2010,
             <https://www.rfc-editor.org/info/rfc5890>.

  [RFC5891]  Klensin, J., "Internationalized Domain Names in
             Applications (IDNA): Protocol", RFC 5891,
             DOI 10.17487/RFC5891, August 2010,
             <https://www.rfc-editor.org/info/rfc5891>.

  [RFC5952]  Kawamura, S. and M. Kawashima, "A Recommendation for IPv6
             Address Text Representation", RFC 5952,
             DOI 10.17487/RFC5952, August 2010,
             <https://www.rfc-editor.org/info/rfc5952>.

  [RFC7230]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
             Protocol (HTTP/1.1): Message Syntax and Routing",
             RFC 7230, DOI 10.17487/RFC7230, June 2014,
             <https://www.rfc-editor.org/info/rfc7230>.

  [RFC7231]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
             Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
             DOI 10.17487/RFC7231, June 2014,
             <https://www.rfc-editor.org/info/rfc7231>.

  [RFC7480]  Newton, A., Ellacott, B., and N. Kong, "HTTP Usage in the
             Registration Data Access Protocol (RDAP)", STD 95,
             RFC 7480, DOI 10.17487/RFC7480, March 2015,
             <https://www.rfc-editor.org/info/rfc7480>.

  [RFC7481]  Hollenbeck, S. and N. Kong, "Security Services for the
             Registration Data Access Protocol (RDAP)", STD 95,
             RFC 7481, DOI 10.17487/RFC7481, March 2015,
             <https://www.rfc-editor.org/info/rfc7481>.

  [RFC7484]  Blanchet, M., "Finding the Authoritative Registration Data
             (RDAP) Service", RFC 7484, DOI 10.17487/RFC7484, March
             2015, <https://www.rfc-editor.org/info/rfc7484>.

  [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
             2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
             May 2017, <https://www.rfc-editor.org/info/rfc8174>.

  [RFC8499]  Hoffman, P., Sullivan, A., and K. Fujiwara, "DNS
             Terminology", BCP 219, RFC 8499, DOI 10.17487/RFC8499,
             January 2019, <https://www.rfc-editor.org/info/rfc8499>.

  [RFC9083]  Hollenbeck, S. and A. Newton, "JSON Responses for the
             Registration Data Access Protocol (RDAP)", STD 95,
             RFC 9083, DOI 10.17487/RFC9083, June 2021,
             <https://www.rfc-editor.org/info/rfc9083>.

  [Unicode-UAX15]
             The Unicode Consortium, "Unicode Standard Annex #15:
             Unicode Normalization Forms", September 2013,
             <https://www.unicode.org/reports/tr15/>.

9.2.  Informative References

  [REST]     Fielding, R., "Architectural Styles and the Design of
             Network-based Software Architectures", Ph.D.
             Dissertation, University of California, Irvine, 2000,
             <https://www.ics.uci.edu/~fielding/pubs/dissertation/
             fielding_dissertation.pdf>.

  [RFC3912]  Daigle, L., "WHOIS Protocol Specification", RFC 3912,
             DOI 10.17487/RFC3912, September 2004,
             <https://www.rfc-editor.org/info/rfc3912>.

  [RFC4007]  Deering, S., Haberman, B., Jinmei, T., Nordmark, E., and
             B. Zill, "IPv6 Scoped Address Architecture", RFC 4007,
             DOI 10.17487/RFC4007, March 2005,
             <https://www.rfc-editor.org/info/rfc4007>.

  [RFC4290]  Klensin, J., "Suggested Practices for Registration of
             Internationalized Domain Names (IDN)", RFC 4290,
             DOI 10.17487/RFC4290, December 2005,
             <https://www.rfc-editor.org/info/rfc4290>.

  [RFC6874]  Carpenter, B., Cheshire, S., and R. Hinden, "Representing
             IPv6 Zone Identifiers in Address Literals and Uniform
             Resource Identifiers", RFC 6874, DOI 10.17487/RFC6874,
             February 2013, <https://www.rfc-editor.org/info/rfc6874>.

  [RFC6927]  Levine, J. and P. Hoffman, "Variants in Second-Level Names
             Registered in Top-Level Domains", RFC 6927,
             DOI 10.17487/RFC6927, May 2013,
             <https://www.rfc-editor.org/info/rfc6927>.

  [RFC8521]  Hollenbeck, S. and A. Newton, "Registration Data Access
             Protocol (RDAP) Object Tagging", BCP 221, RFC 8521,
             DOI 10.17487/RFC8521, November 2018,
             <https://www.rfc-editor.org/info/rfc8521>.

Appendix A.  Changes from RFC 7482

  *  Addressed known errata.

  *  Addressed other reported clarifications and corrections: IDN,
     IDNA, and DNR definitions.  Noted that registrars are entities.
     Added a reference to RFC 8521 to address the bootstrap registry
     limitation.  Removed extraneous "...".  Clarified HTTP query
     string, search pattern, name server search, domain label suffix,
     and asterisk search.

  *  Addressed "The HTTP query string" clarification.

  *  Modified coauthor address.

  *  Updated references to RFC 7483 to RFC 9083.

  *  Added an IANA Considerations section.  Changed references to use
     HTTPS for targets.

  *  Changed "XXXX is a search pattern representing the "FN" property
     of an entity (such as a contact, registrant, or registrar) name as
     specified in Section 5.1" to "Changed "XXXX is a search pattern
     representing the "fn" property of an entity (such as a contact,
     registrant, or registrar) name as described in Section 5.1".

  *  Added acknowledgments.

  *  Changed "The intent of the patterns described here are to enable
     queries" to "The intent of the patterns described here is to
     enable queries".

  *  Changed "the corresponding syntax extension in RFC 6874 [RFC6874]
     MUST NOT be used, and servers are to ignore it if possible" to
     "the corresponding syntax extension in RFC 6874 [RFC6874] MUST NOT
     be used, and servers SHOULD ignore it".

  *  Changed "Only a single asterisk is allowed for a partial string
     search" to "A partial string search MUST NOT include more than one
     asterisk".

  *  Changed "Clients should avoid submitting a partial match search of
     Unicode characters where a Unicode character may be legally
     combined with another Unicode character or characters" to "Clients
     SHOULD NOT submit a partial match search of Unicode characters
     where a Unicode character may be legally combined with another
     Unicode character or characters".

  *  Changed description of nameserver IP address "search pattern" in
     Sections 3.2.1 and 3.2.2.

  *  IESG review feedback: Added "obsoletes 7482" to the headers,
     Abstract, and Introduction.  Changed "IETF standards" to "IETF
     specifications" and "Therefore" to "Accordingly" in Section 1.
     Updated the BCP 14 boilerplate.  Added definition of "bootstrap
     registry" and changed "concatenating ... to" to "concatenating ...
     with" in Section 3.  Changed "bitmask length" to "prefix length"
     and "2001:db8::0" to "2001:db8::" in Section 3.1.1.  Added "in
     contrast to the more generic HTTP query string that admits
     multiple simultaneous parameters" in Section 3.2.  Changed
     "0x002A" to "0x2A" in Section 4.1.  Clarified use of HTTP 422
     SHOULD in Section 4.1.

Acknowledgments

  This document is derived from original work on RIR query formats
  developed by Byron J. Ellacott of APNIC, Arturo L. Servin of LACNIC,
  Kaveh Ranjbar of the RIPE NCC, and Andrew L. Newton of ARIN.
  Additionally, this document incorporates DNR query formats originally
  described by Francisco Arias and Steve Sheng of ICANN and Scott
  Hollenbeck of Verisign Labs.

  The authors would like to acknowledge the following individuals for
  their contributions to this document: Francisco Arias, Marc Blanchet,
  Ernie Dainow, Jean-Philippe Dionne, Byron J. Ellacott, Behnam
  Esfahbod, John Klensin, John Levine, Edward Lewis, Mario Loffredo,
  Patrick Mevzek, Mark Nottingham, Kaveh Ranjbar, Arturo L. Servin,
  Steve Sheng, Jasdip Singh, and Andrew Sullivan.

Authors' Addresses

  Scott Hollenbeck
  Verisign Labs
  12061 Bluemont Way
  Reston, VA 20190
  United States of America

  Email: [email protected]
  URI:   https://www.verisignlabs.com/


  Andy Newton
  Amazon Web Services, Inc.
  13200 Woodland Park Road
  Herndon, VA 20171
  United States of America

  Email: [email protected]

=========================================================================



Internet Engineering Task Force (IETF)                     S. Hollenbeck
Request for Comments: 9083                                 Verisign Labs
STD: 95                                                        A. Newton
Obsoletes: 7483                                                      AWS
Category: Standards Track                                      June 2021
ISSN: 2070-1721


   JSON Responses for the Registration Data Access Protocol (RDAP)

Abstract

  This document describes JSON data structures representing
  registration information maintained by Regional Internet Registries
  (RIRs) and Domain Name Registries (DNRs).  These data structures are
  used to form Registration Data Access Protocol (RDAP) query
  responses.  This document obsoletes RFC 7483.

Status of This Memo

  This is an Internet Standards Track document.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Further information on
  Internet Standards is available in Section 2 of RFC 7841.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  https://www.rfc-editor.org/info/rfc9083.

Copyright Notice

  Copyright (c) 2021 IETF Trust and the persons identified as the
  document authors.  All rights reserved.

  This document is subject to BCP 78 and the IETF Trust's Legal
  Provisions Relating to IETF Documents
  (https://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.

Table of Contents

  1.  Introduction
    1.1.  Terminology and Definitions
    1.2.  Data Model
  2.  Use of JSON
    2.1.  Naming
  3.  Common Data Types
  4.  Common Data Structures
    4.1.  RDAP Conformance
    4.2.  Links
    4.3.  Notices and Remarks
    4.4.  Language Identifier
    4.5.  Events
    4.6.  Status
    4.7.  Port 43 WHOIS Server
    4.8.  Public IDs
    4.9.  Object Class Name
    4.10. An Example
  5.  Object Classes
    5.1.  The Entity Object Class
    5.2.  The Nameserver Object Class
    5.3.  The Domain Object Class
    5.4.  The IP Network Object Class
    5.5.  The Autonomous System Number Object Class
  6.  Error Response Body
  7.  Responding to Help Queries
  8.  Responding To Searches
  9.  Indicating Truncated Responses
  10. IANA Considerations
    10.1.  RDAP JSON Media Type Registration
    10.2.  JSON Values Registry
      10.2.1.  Notice and Remark Types
      10.2.2.  Status
      10.2.3.  Event Actions
      10.2.4.  Roles
      10.2.5.  Variant Relations
  11. Security Considerations
  12. Internationalization Considerations
    12.1.  Character Encoding
    12.2.  URIs and IRIs
    12.3.  Language Tags
    12.4.  Internationalized Domain Names
  13. Privacy Considerations
  14. References
    14.1.  Normative References
    14.2.  Informative References
  Appendix A.  Suggested Data Modeling with the Entity Object Class
    A.1.  Registrants and Contacts
    A.2.  Registrars
  Appendix B.  Modeling Events
  Appendix C.  Structured vs. Unstructured Addresses
  Appendix D.  Secure DNS
  Appendix E.  Motivations for Using JSON
  Appendix F.  Changes from RFC 7483
  Acknowledgments
  Authors' Addresses

1.  Introduction

  This document describes responses in the JSON [RFC8259] format for
  the queries as defined by the Registration Data Access Protocol Query
  Format [RFC9082].  A communication protocol for exchanging queries
  and responses is described in [RFC7480].  This document obsoletes RFC
  7483.

1.1.  Terminology and Definitions

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
  "OPTIONAL" in this document are to be interpreted as described in
  BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
  capitals, as shown here.

  The following list describes terminology and definitions used
  throughout this document:

  DNR:  Domain Name Registry or Domain Name Registrar

  LDH:  letters, digits, hyphen

  member:  data found within an object as defined by JSON [RFC8259]

  object:  a data structure as defined by JSON [RFC8259]

  object class:  the definition of members that may be found in JSON
   objects described in this document

  object instance:  an instantiation or specific instance of an object
   class

  RDAP:  Registration Data Access Protocol

  RIR:  Regional Internet Registry

1.2.  Data Model

  The data model for JSON responses is specified in five sections:

  1.  simple data types conveyed in JSON primitive types (strings,
      numbers, booleans, and null)

  2.  data structures specified as JSON arrays or objects that are used
      repeatedly when building up larger objects

  3.  object classes representing structured data corresponding to a
      lookup of a single object

  4.  arrays of objects representing structured data corresponding to a
      search for multiple objects

  5.  the response to an error

  The object classes represent responses for two major categories of
  data: responses returned by RIRs for registration data related to IP
  addresses, reverse DNS names, and Autonomous System numbers and
  responses returned by DNRs for registration data related to forward
  DNS names.  The following object classes are returned by both RIRs
  and DNRs:

  1.  domains

  2.  nameservers

  3.  entities

  The information served by both RIRs and DNRs for these object classes
  overlap extensively and are given in this document as a unified model
  for both classes of service.

  In addition to the object classes listed above, RIRs also serve the
  following object classes:

  1.  IP networks

  2.  Autonomous System numbers

  Object classes defined in this document represent a minimal set of
  what a compliant client/server needs to understand to function
  correctly; however, some deployments may want to include additional
  object classes to suit individual needs.  Anticipating this need for
  extension, Section 2.1 of this document defines a mechanism for
  extending the JSON objects that are described in this document.

  Positive responses take two forms.  A response to a lookup of a
  single object in the registration system yields a JSON object, which
  is the subject of the lookup.  A response to a search for multiple
  objects yields a JSON object that contains an array of JSON objects
  that are the subject of the search.  In each type of response, other
  data structures are present within the topmost JSON object.

2.  Use of JSON

2.1.  Naming

  Clients of these JSON responses SHOULD ignore unrecognized JSON
  members in responses.  Servers can insert members into the JSON
  responses, which are not specified in this document, but that does
  not constitute an error in the response.  Servers that insert such
  unspecified members into JSON responses SHOULD have member names
  prefixed with a short identifier followed by an underscore followed
  by a meaningful name.  It has been observed that these short
  identifiers aid software implementers with identifying the
  specification of the JSON member, and failure to use one could cause
  an implementer to assume the server is erroneously using a name from
  this specification.  This allowance does not apply to jCard [RFC7095]
  objects.  The full JSON name (the prefix plus the underscore plus the
  meaningful name) SHOULD adhere to the character and name limitations
  of the prefix registry described in [RFC7480].  Failure to use these
  limitations could result in slower adoption as these limitations have
  been observed to aid some client programming models.

  Consider the following JSON response with JSON members, all of which
  are specified in this document.

  {
    "handle" : "ABC123",
    "remarks" :
    [
      {
        "description" :
        [
          "She sells sea shells down by the sea shore.",
          "Originally written by Terry Sullivan."
        ]
      }
    ]
  }

                                 Figure 1

  If The Registry of the Moon desires to express information not found
  in this specification, it might select "lunarNIC" as its identifying
  prefix and insert, as an example, the member named
  "lunarNIC_beforeOneSmallStep" to signify registrations occurring
  before the first moon landing and the member named
  "lunarNIC_harshMistressNotes" that contains other descriptive text.

  Consider the following JSON response with JSON names, some of which
  should be ignored by clients without knowledge of their meaning.

  {
    "handle" : "ABC123",
    "lunarNIC_beforeOneSmallStep" : "TRUE THAT!",
    "remarks" :
    [
      {
        "description" :
        [
          "She sells sea shells down by the sea shore.",
          "Originally written by Terry Sullivan."
        ]
      }
    ],
    "lunarNIC_harshMistressNotes" :
    [
      "In space,",
      "nobody can hear you scream."
    ]
  }

                                 Figure 2

  Insertion of unrecognized members ignored by clients may also be used
  for future revisions to this specification.

  Clients processing JSON responses need to be prepared for members
  representing registration data specified in this document to be
  absent from a response.  In other words, servers are free to omit
  unrequired/optional JSON members containing registration data based
  on their own policies.

  Finally, all JSON names specified in this document are case
  sensitive.  Both servers and clients MUST transmit and process them
  using the specified character case.

3.  Common Data Types

  JSON [RFC8259] defines the data types of a number, character string,
  boolean, array, object, and null.  This section describes the
  semantics and/or syntax reference for common, JSON character strings
  used in this document.

  handle:           DNRs and RIRs have registry-unique identifiers that
                    may be used to specifically reference an object
                    instance.  The semantics of this data type as found
                    in this document are to be a registry-unique
                    reference to the closest enclosing object where the
                    value is found.  The data type names "registryId",
                    "roid", "nic-handle", "registrationNo", etc., are
                    terms often synonymous with this data type.  In
                    this document, the term "handle" is used.  The term
                    exposed to users by clients is a presentation issue
                    beyond the scope of this document.  This value is a
                    simple character string.

  IPv4 addresses:   The representation of IPv4 addresses in this
                    document uses the dotted-decimal notation.  An
                    example of this textual representation is
                    "192.0.2.0".

  IPv6 addresses:   The representation of IPv6 addresses in this
                    document follow the forms outlined in [RFC5952].
                    An example of this textual representation is
                    "2001:db8::1:0:0:1".

  country codes:    Where the identity of a geopolitical nation or
                    country is needed, these identities are represented
                    with the alpha-2 or two-character country code
                    designation as defined in [ISO.3166.2020].  The
                    alpha-2 representation is used because it is freely
                    available, whereas the alpha-3 and numeric-3
                    standards are not.

  LDH names:        Textual representations of DNS names where the
                    labels of the domain are all "letters, digits,
                    hyphen" labels as described by [RFC5890].  Trailing
                    periods are optional.

  Unicode names:    Textual representations of DNS names where one or
                    more of the labels are U-labels as described by
                    [RFC5890].  Trailing periods are optional.

  dates and times:  The syntax for values denoting dates and times is
                    defined in [RFC3339].

  URIs:             The syntax for values denoting a Uniform Resource
                    Identifier (URI) is defined by [RFC3986].

  Contact information is defined using jCards as described in
  [RFC7095].  The "fn" member is required and MUST NOT be null
  according to [RFC6350].  An empty "fn" member MAY be used when the
  contact name does not exist or is redacted.

4.  Common Data Structures

  This section defines common data structures used in responses and
  object classes.

4.1.  RDAP Conformance

  The data structure named "rdapConformance" is an array of strings,
  each providing a hint as to the specifications used in the
  construction of the response.  This data structure MUST appear in the
  topmost JSON object of a response and MUST NOT appear anywhere else.
  A response to a "help" request will include identifiers for all of
  the specifications supported by the server.  A response to any other
  request will include only identifiers for the specifications used in
  the construction of the response.  The set of returned identifiers
  MAY vary depending on the authorization level of the client.

  An example rdapConformance data structure:

  "rdapConformance" :
  [
    "rdap_level_0"
  ]

                                 Figure 3

  The string literal "rdap_level_0" signifies conformance with this
  specification.  When custom JSON values are inserted into responses,
  conformance to those custom specifications MUST be indicated by
  including a unique string literal value registered in the IANA RDAP
  Extensions registry specified in [RFC7480].  For example, if the
  fictional Registry of the Moon wants to signify that their JSON
  responses are conformant with their registered extensions, the string
  used might be "lunarNIC_level_0".  These registered values aid the
  identification of specifications for software implementers, and
  failure to use them could result in slower adoption of extensions.

  Example rdapConformance structure with custom extensions noted:

  "rdapConformance" :
  [
    "rdap_level_0",
    "lunarNIC_level_0"
  ]

                                 Figure 4

4.2.  Links

  The "links" array is found in data structures to signify links to
  other resources on the Internet.  The relationship of these links is
  defined by the IANA registry described by [RFC8288].

  The following is an example of the link structure:

      {
        "value" : "https://example.com/context_uri",
        "rel" : "self",
        "href" : "https://example.com/target_uri",
        "hreflang" : [ "en", "ch" ],
        "title" : "title",
        "media" : "screen",
        "type" : "application/json"
      }

                                 Figure 5

  The JSON name/values of "rel", "href", "hreflang", "title", "media",
  and "type" correspond to values found in Section 3 of [RFC8288].  The
  "value" JSON value is the context URI as described by [RFC8288].  The
  "value", "rel", and "href" JSON values MUST be specified.  All other
  JSON values are OPTIONAL.  A "related" link relation MUST NOT include
  an "href" URI that is the same as the "self" link relation "href" URI
  to reduce the risk of infinite client processing loops.
  Internationalized Domain Names (IDNs) returned in URIs SHOULD be
  consistently returned in LDH name format to allow clients to process
  these IDNs according to their capabilities.

  This is an example of the "links" array as it might be found in an
  object class:

      "links" :
      [
          {
            "value" : "https://example.com/ip/2001:db8::123",
            "rel" : "self",
            "href" : "https://example.com/ip/2001:db8::123",
            "type" : "application/rdap+json"
          },
          {
            "value" : "https://example.com/ip/2001:db8::123",
            "rel" : "up",
            "href" : "https://example.com/ip/2001:db8::/48",
            "type" : "application/rdap+json"
          }

      ]

                                 Figure 6

4.3.  Notices and Remarks

  The "notices" and "remarks" data structures take the same form.  The
  notices structure denotes information about the service providing
  RDAP information and/or information about the entire response,
  whereas the remarks structure denotes information about the object
  class that contains it (see Section 5 regarding object classes).

  Both are arrays of objects.  Each object contains a "title" string
  representing the title of the object, a "type" string denoting a
  registered type of remark or notice (see Section 10.2.1), an array of
  strings named "description" for the purposes of conveying any
  descriptive text, and a "links" array as described in Section 4.2.
  The "description" array MUST be included.  All other JSON values are
  OPTIONAL.

  An example of the notices data structure:

  "notices" :
  [
    {
      "title" : "Terms of Use",
      "description" :
      [
        "Service subject to The Registry of the Moon's TOS.",
        "Copyright (c) 2020 LunarNIC"
      ],
      "links" :
      [
        {
          "value" : "https://example.net/entity/XXXX",
          "rel" : "alternate",
          "type" : "text/html",
          "href" : "https://www.example.com/terms_of_use.html"
        }
      ]
    }
  ]

                                 Figure 7

  It is the job of the clients to determine line breaks, spacing, and
  display issues for sentences within the character strings of the
  "description" array.  Each string in the "description" array contains
  a single complete division of human-readable text indicating to
  clients where there are semantic breaks.

  An example of the remarks data structure:

  "remarks" :
  [
    {
      "description" :
      [
        "She sells sea shells down by the sea shore.",
        "Originally written by Terry Sullivan."
      ]
    }
  ]

                                 Figure 8

  Note that objects in the "remarks" array may also have a "links"
  array.

  While the "title" and "description" fields are intended primarily for
  human consumption, the "type" string contains a well-known value to
  be registered with IANA (see Section 10.2.1) for programmatic use.

  An example of the remarks data structure:

  "remarks" :
  [
    {
      "type" : "object truncated due to authorization",
      "description" :
      [
        "Some registration data may not have been given.",
        "Use proper authorization credentials to see all of it."
      ]
    }
  ]

                                 Figure 9

  While the "remarks" array will appear in many object classes in a
  response, the "notices" array appears only in the topmost object of a
  response.

4.4.  Language Identifier

  This data structure consists solely of a name/value pair, where the
  name is "lang" and the value is a string containing a language
  identifier as described in [RFC5646].

  "lang" : "mn-Cyrl-MN"

                                Figure 10

  The "lang" attribute as defined in this section MAY appear anywhere
  in an object class or data structure, except for in jCard objects.
  vCard supports similar functionality by way of the LANGUAGE property
  parameter (see Section 5.1 of RFC 6350 [RFC6350]).

4.5.  Events

  This data structure represents events that have occurred on an
  instance of an object class (see Section 5 regarding object classes).

  This is an example of an "events" array.

  "events" :
  [
    {
      "eventAction" : "registration",
      "eventActor" : "SOMEID-LUNARNIC",
      "eventDate" : "1990-12-31T23:59:59Z"
    },
    {
      "eventAction" : "last changed",
      "eventActor" : "OTHERID-LUNARNIC",
      "eventDate" : "1991-12-31T23:59:59Z"
    }
  ]

                                Figure 11

  The "events" array consists of objects, each with the following
  members:

  *  "eventAction" -- a REQUIRED string denoting the reason for the
     event

  *  "eventActor" -- an OPTIONAL identifier denoting the actor
     responsible for the event

  *  "eventDate" -- a REQUIRED string containing the time and date the
     event occurred

  *  "links" -- OPTIONAL; see Section 4.2

  Events can be future dated.  One use case for future dating of events
  is to denote when an object expires from a registry.

  The "links" array in this data structure is provided for references
  to the event actor.  In order to reference an RDAP entity, a "rel" of
  "related" and a "type" of "application/rdap+json" is used in the link
  reference.

  See Section 10.2.3 for a list of values for the "eventAction" string.
  See Appendix B regarding the various ways events can be modeled.

4.6.  Status

  This data structure, named "status", is an array of strings
  indicating the state of a registered object (see Section 10.2.2 for a
  list of values).

4.7.  Port 43 WHOIS Server

  This data structure, a member named "port43", is a simple character
  string containing the fully qualified host name or IP address of the
  WHOIS [RFC3912] server where the containing object instance may be
  found.  Note that this is not a URI, as there is no WHOIS URI scheme.

4.8.  Public IDs

  This data structure maps a public identifier to an object class.  It
  is named "publicIds" and is an array of objects, with each object
  containing the following REQUIRED members:

  *  type -- a string denoting the type of public identifier

  *  identifier -- a string denoting a public identifier of the type
     related to "type"

  The following is an example of a publicIds structure.

  "publicIds":
  [
    {
      "type":"IANA Registrar ID",
      "identifier":"1"
    }
  ]

                                Figure 12

4.9.  Object Class Name

  This data structure, a member named "objectClassName", gives the
  object class name of a particular object as a string.  This
  identifies the type of object being processed.  An objectClassName is
  REQUIRED in all RDAP response objects so that the type of the object
  can be interpreted.

4.10.  An Example

  This is an example response with both rdapConformance and notices
  embedded:

  {
    "rdapConformance" :
    [
      "rdap_level_0"
    ],
    "notices" :
    [
      {
        "title" : "Content Removed",
        "description" :
        [
          "Without full authorization, content has been removed.",
          "Sorry, dude!"
        ],
        "links" :
        [
          {
            "value" : "https://example.net/ip/192.0.2.0/24",
            "rel" : "alternate",
            "type" : "text/html",
            "href" : "https://www.example.com/redaction_policy.html"
          }
        ]
      }
    ],
    "lang" : "en",
    "objectClassName" : "ip network",
    "startAddress" : "192.0.2.0",
    "endAddress" : "192.0.2.255",
    "handle" : "XXXX-RIR",
    "ipVersion" : "v4",
    "name": "NET-RTR-1",
    "parentHandle" : "YYYY-RIR",
    "remarks" :
    [

      {
        "description" :
        [
          "She sells sea shells down by the sea shore.",
          "Originally written by Terry Sullivan."
        ]
      }
    ]
  }

                                Figure 13

5.  Object Classes

  Object classes represent structures appropriate for a response from
  the queries specified in [RFC9082].

  Each object class contains a "links" array as specified in
  Section 4.2.  For every object class instance in a response, whether
  the object class instance is directly representing the response to a
  query or is embedded in other object class instances or is an item in
  a search result set, servers SHOULD provide a link representing a URI
  for that object class instance using the "self" relationship as
  described in the IANA registry specified by [RFC8288].  As explained
  in Section 5.2, this may be not always be possible for nameserver
  data.  Clients MUST be able to process object instances without a
  self link.  When present, clients can use the self link for caching
  data.  Servers MAY provide more than one self link for any given
  object instance.  Failure to provide any self link by a server may
  result in clients being unable to cache object class instances.

  Clients using self links for caching SHOULD NOT cache any object
  class instances where the authority of the self link is different
  than the authority of the server returning the data.  Failing to do
  so might result in cache poisoning.

  Self links MUST contain a "type" element containing the "application/
  rdap+json" media type when referencing RDAP object instances as
  defined by this document.

  This is an example of the "links" array with a self link to an object
  class:

      "links" :
      [
          {
            "value" : "https://example.com/ip/2001:db8::123",
            "rel" : "self",
            "href" : "https://example.com/ip/2001:db8::123",
            "type" : "application/rdap+json"
          }
      ]

                                Figure 14

5.1.  The Entity Object Class

  The entity object class appears throughout this document and is an
  appropriate response for the /entity/XXXX query defined in
  "Registration Data Access Protocol (RDAP) Query Format" [RFC9082].
  This object class represents the information of organizations,
  corporations, governments, non-profits, clubs, individual persons,
  and informal groups of people.  All of these representations are so
  similar that it is best to represent them in JSON [RFC8259] with one
  construct, the entity object class, to aid in the reuse of code by
  implementers.

  The entity object class uses jCard [RFC7095] to represent contact
  information, such as postal addresses, email addresses, phone numbers
  and names of organizations and individuals.  Many of the types of
  information that can be represented with jCard have little or no use
  in RDAP, such as birthdays, anniversaries, and gender.

  The entity object is served by both RIRs and DNRs.  The following is
  an example of an entity that might be served by an RIR.

  {
    "objectClassName" : "entity",
    "handle":"XXXX",
    "vcardArray":[
      "vcard",
      [
        ["version", {}, "text", "4.0"],
        ["fn", {}, "text", "Joe User"],
        ["n", {}, "text",
          ["User", "Joe", "", "", ["ing. jr", "M.Sc."]]
        ],
        ["kind", {}, "text", "individual"],
        ["lang", {
          "pref":"1"
        }, "language-tag", "fr"],
        ["lang", {
          "pref":"2"
        }, "language-tag", "en"],
        ["org", {
          "type":"work"
        }, "text", "Example"],
        ["title", {}, "text", "Research Scientist"],
        ["role", {}, "text", "Project Lead"],
        ["adr",
          { "type":"work" },
          "text",
          [
            "",
            "Suite 1234",
            "4321 Rue Somewhere",
            "Quebec",
            "QC",
            "G1V 2M2",
            "Canada"
          ]
        ],
        ["adr",
          {
            "type":"home",
            "label":"123 Maple Ave\nSuite 90001\nVancouver\nBC\n1239\n"
          },
          "text",
          [
            "", "", "", "", "", "", ""
          ]
        ],
        ["tel",
          {
            "type":["work", "voice"],
            "pref":"1"
          },
          "uri",
          "tel:+1-555-555-1234;ext=102"
        ],
        ["tel",
          { "type":["work", "cell", "voice", "video", "text"] },
          "uri",
          "tel:+1-555-555-4321"
        ],
        ["email",
          { "type":"work" },
          "text",
          "[email protected]"
        ],
        ["geo", {
          "type":"work"
        }, "uri", "geo:46.772673,-71.282945"],
        ["key",
          { "type":"work" },
          "uri",
          "https://www.example.com/joe.user/joe.asc"
        ],
        ["tz", {},
          "utc-offset", "-05:00"],
        ["url", { "type":"home" },
          "uri", "https://example.org"]
      ]
    ],
    "roles":[ "registrar" ],
    "publicIds":[
      {
        "type":"IANA Registrar ID",
        "identifier":"1"
      }
    ],
    "remarks":[
      {
        "description":[
          "She sells sea shells down by the sea shore.",
          "Originally written by Terry Sullivan."
        ]
      }
    ],
    "links":[
      {
        "value":"https://example.com/entity/XXXX",
        "rel":"self",
        "href":"https://example.com/entity/XXXX",
        "type" : "application/rdap+json"
      }
    ],
    "events":[
      {
        "eventAction":"registration",
        "eventDate":"1990-12-31T23:59:59Z"
      }
    ],
    "asEventActor":[

      {
        "eventAction":"last changed",
        "eventDate":"1991-12-31T23:59:59Z"
      }
    ]
  }

                                Figure 15

  The entity object class can contain the following members:

  *  objectClassName -- the string "entity"

  *  handle -- a string representing a registry-unique identifier of
     the entity

  *  vcardArray -- a jCard with the entity's contact information

  *  roles -- an array of strings, each signifying the relationship an
     object would have with its closest containing object (see
     Section 10.2.4 for a list of values)

  *  publicIds -- see Section 4.8

  *  entities -- an array of entity objects as defined by this section

  *  remarks -- see Section 4.3

  *  links -- see Section 4.2

  *  events -- see Section 4.5

  *  asEventActor -- this data structure takes the same form as the
     events data structure (see Section 4.5), but each object in the
     array MUST NOT have an "eventActor" member.  These objects denote
     that the entity is an event actor for the given events.  See
     Appendix B regarding the various ways events can be modeled.

  *  status -- see Section 4.6

  *  port43 -- see Section 4.7

  *  networks -- an array of IP network objects as defined in
     Section 5.4

  *  autnums -- an array of autnum objects as defined in Section 5.5

  Entities may also have other entities embedded with them in an array.
  This can be used to model an organization with specific individuals
  fulfilling designated roles of responsibility.

  The following is an elided example of an entity with embedded
  entities.

  {
    "objectClassName" : "entity",
    "handle" : "ANENTITY",
    "roles" : [ "registrar" ],
    ...
    "entities" :
    [
      {
        "objectClassName" : "entity",
        "handle": "ANEMBEDDEDENTITY",
        "roles" : [ "technical" ],
        ...
      },
      ...
    ],
    ...
  }

                                Figure 16

  The following is an example of an entity that might be served by a
  DNR.

  {
    "objectClassName" : "entity",
    "handle":"XXXX",
    "vcardArray":[
      "vcard",
      [
        ["version", {}, "text", "4.0"],
        ["fn", {}, "text", "Joe User"],
        ["kind", {}, "text", "individual"],
        ["lang", {
          "pref":"1"
        }, "language-tag", "fr"],
        ["lang", {
          "pref":"2"
        }, "language-tag", "en"],
        ["org", {
          "type":"work"
        }, "text", "Example"],
        ["title", {}, "text", "Research Scientist"],
        ["role", {}, "text", "Project Lead"],
        ["adr",
          { "type":"work" },
          "text",
          [
            "",
            "Suite 1234",
            "4321 Rue Somewhere",
            "Quebec",
            "QC",
            "G1V 2M2",
            "Canada"
          ]
        ],
        ["tel",
          { "type":["work", "voice"], "pref":"1" },
          "uri", "tel:+1-555-555-1234;ext=102"
        ],
        ["email",
          { "type":"work" },
          "text", "[email protected]"
        ]
      ]
    ],
    "status":[ "validated", "locked" ],
    "remarks":[
      {
        "description":[
          "She sells sea shells down by the sea shore.",
          "Originally written by Terry Sullivan."
        ]
      }
    ],
    "links":[
      {
        "value":"https://example.com/entity/XXXX",
        "rel":"self",
        "href":"https://example.com/entity/XXXX",
        "type":"application/rdap+json"
      }
    ],
    "port43":"whois.example.net",
    "events":[
      {
        "eventAction":"registration",
        "eventDate":"1990-12-31T23:59:59Z"
      },
      {
        "eventAction":"last changed",
        "eventDate":"1991-12-31T23:59:59Z",
        "eventActor":"[email protected]"
      }
    ]
  }

                                Figure 17

  See Appendix A for use of the entity object class to model various
  types of entities found in both RIRs and DNRs.  See Appendix C
  regarding structured vs.  unstructured postal addresses in entities.

5.2.  The Nameserver Object Class

  The nameserver object class represents information regarding DNS
  nameservers used in both forward and reverse DNS.  RIRs and some DNRs
  register or expose nameserver information as an attribute of a domain
  name, while other DNRs model nameservers as "first class objects".
  Please note that some of the examples in this section include lines
  that have been wrapped for reading clarity.

  The nameserver object class accommodates both models and degrees of
  variation in between.

  The following is an example of a nameserver object.

    {
      "objectClassName" : "nameserver",
      "handle" : "XXXX",
      "ldhName" : "ns1.xn--fo-5ja.example",
      "unicodeName" : "ns.fóo.example",
      "status" : [ "active" ],
      "ipAddresses" :
      {
        "v4": [ "192.0.2.1", "192.0.2.2" ],
        "v6": [ "2001:db8::123" ]
      },
      "remarks" :
      [
        {
          "description" :
          [
            "She sells sea shells down by the sea shore.",
            "Originally written by Terry Sullivan."
          ]
        }
      ],
      "links" :
      [
        {
          "value" : "https://example.net/nameserver/
                     ns1.xn--fo-5ja.example",
          "rel" : "self",
          "href" : "https://example.net/nameserver/
                    ns1.xn--fo-5ja.example",
          "type" : "application/rdap+json"
        }
      ],
      "port43" : "whois.example.net",
      "events" :
      [
        {
          "eventAction" : "registration",
          "eventDate" : "1990-12-31T23:59:59Z"
        },
        {
          "eventAction" : "last changed",
          "eventDate" : "1991-12-31T23:59:59Z",
          "eventActor" : "[email protected]"
        }
      ]
    }

                                Figure 18

  Figure 18 is an example of a nameserver object with all appropriate
  values given.  Registries using a first-class nameserver data model
  would embed this in domain objects as well as allowing references to
  it with the "/nameserver" query type (all depending on the registry
  operators policy).  Other registries may pare back the information as
  needed.  Figure 19 is an example of a nameserver object as would be
  found in RIRs and some DNRs, while Figure 20 is an example of a
  nameserver object as would be found in other DNRs.

  The following is an example of the simplest nameserver object:

    {
      "objectClassName" : "nameserver",
      "ldhName" : "ns1.example.com"
    }

                                Figure 19

  The following is an example of a simple nameserver object that might
  be commonly used by DNRs:

    {
      "objectClassName" : "nameserver",
      "ldhName" : "ns1.example.com",
      "ipAddresses" : { "v6" : [ "2001:db8::123", "2001:db8::124" ] }
    }

                                Figure 20

  As nameservers can be modeled by some registries to be first-class
  objects, they may also have an array of entities (Section 5.1)
  embedded to signify parties responsible for the maintenance,
  registrations, etc., of the nameservers.

  The following is an elided example of a nameserver with embedded
  entities.

  {
    "objectClassName" : "nameserver",
    "handle" : "XXXX",
    "ldhName" : "ns.xn--fo-5ja.example",
    ...
    "entities" :
    [
      ...
    ],
    ...
  }

                                Figure 21

  The nameserver object class can contain the following members:

  *  objectClassName -- the string "nameserver"

  *  handle -- a string representing a registry-unique identifier of
     the nameserver

  *  ldhName -- a string containing the LDH name of the nameserver (see
     Section 3)

  *  unicodeName -- a string containing a DNS Unicode name of the
     nameserver (see Section 3)

  *  ipAddresses -- an object containing the following members:

     -  v6 -- an array of strings containing IPv6 addresses of the
        nameserver

     -  v4 -- an array of strings containing IPv4 addresses of the
        nameserver

  *  entities -- an array of entity objects as defined by Section 5.1

  *  status -- see Section 4.6

  *  remarks -- see Section 4.3

  *  links -- see Section 4.2

  *  port43 -- see Section 4.7

  *  events -- see Section 4.5

5.3.  The Domain Object Class

  The domain object class represents a DNS name and point of
  delegation.  For RIRs, these delegation points are in the reverse DNS
  tree, whereas for DNRs, these delegation points are in the forward
  DNS tree.

  In both cases, the high-level structure of the domain object class
  consists of information about the domain registration, nameserver
  information related to the domain name, and entities related to the
  domain name (e.g., registrant information, contacts, etc.).

  The following is an elided example of the domain object showing the
  high-level structure:

  {
    "objectClassName" : "domain",
    "handle" : "XXX",
    "ldhName" : "blah.example.com",
    ...
    "nameservers" :
    [
      ...
    ],
    ...
    "entities" :
    [
      ...
    ]
  }

                                Figure 22

  The domain object class can contain the following members:


  *  objectClassName -- the string "domain"

  *  handle -- a string representing a registry-unique identifier of
     the domain object instance

  *  ldhName -- a string describing a domain name in LDH form as
     described in Section 3

  *  unicodeName -- a string containing a domain name with U-labels as
     described in Section 3

  *  variants -- an array of objects, each containing the following
     values:

     -  relation -- an array of strings, with each string denoting the
        relationship between the variants and the containing domain
        object (see Section 10.2.5 for a list of suggested variant
        relations).

     -  idnTable -- the character string literal that represents the
        Internationalized Domain Name (IDN) table that has been
        registered in the IANA Repository of IDN Practices
        [IANA_IDNTABLES].

     -  variantNames -- an array of objects, with each object
        containing an "ldhName" member and a "unicodeName" member (see
        Section 3).

  *  nameservers -- an array of nameserver objects as defined by
     Section 5.2

  *  secureDNS -- an object with the following members:

     -  zoneSigned -- boolean true if the zone has been signed, false
        otherwise.

     -  delegationSigned -- boolean true if there are DS records in the
        parent, false otherwise.

     -  maxSigLife -- an integer representing the signature lifetime in
        seconds to be used when creating the RRSIG DS record in the
        parent zone [RFC5910].

     -  dsData -- an array of objects, each with the following members:

        o  keyTag -- an integer as specified by the key tag field of a
           DNS DS record as specified by [RFC4034] in presentation
           format

        o  algorithm -- an integer as specified by the algorithm field
           of a DNS DS record as described by RFC 4034 in presentation
           format

        o  digest -- a string as specified by the digest field of a DNS
           DS record as specified by RFC 4034 in presentation format

        o  digestType -- an integer as specified by the digest type
           field of a DNS DS record as specified by RFC 4034 in
           presentation format

        o  events -- see Section 4.5

        o  links -- see Section 4.2

     -  keyData -- an array of objects, each with the following
        members:

        o  flags -- an integer representing the flags field value in
           the DNSKEY record [RFC4034] in presentation format

        o  protocol -- an integer representation of the protocol field
           value of the DNSKEY record [RFC4034] in presentation format

        o  publicKey -- a string representation of the public key in
           the DNSKEY record [RFC4034] in presentation format

        o  algorithm -- an integer as specified by the algorithm field
           of a DNSKEY record as specified by [RFC4034] in presentation
           format

        o  events -- see Section 4.5

        o  links -- see Section 4.2

           See Appendix D for background information on these objects.

  *  entities -- an array of entity objects as defined by Section 5.1

  *  status -- see Section 4.6

  *  publicIds -- see Section 4.8

  *  remarks -- see Section 4.3

  *  links -- see Section 4.2

  *  port43 -- see Section 4.7

  *  events -- see Section 4.5

  *  network -- represents the IP network for which a reverse DNS
     domain is referenced; see Section 5.4

  The following is an example of a JSON domain object representing a
  reverse DNS delegation point that might be served by an RIR (note
  that the dsData digest value has been modified to fit on one line).

  {
    "objectClassName" : "domain",
    "handle" : "XXXX",
    "ldhName" : "0.2.192.in-addr.arpa",
    "nameservers" :
    [
      {
        "objectClassName" : "nameserver",
        "ldhName" : "ns1.rir.example"
      },
      {
        "objectClassName" : "nameserver",
        "ldhName" : "ns2.rir.example"
      }
    ],
    "secureDNS":
    {
      "delegationSigned": true,
      "dsData":
      [
        {
          "keyTag": 25345,
          "algorithm": 8,
          "digestType": 2,
          "digest": "2788970E18EA14...C890C85B8205B94"
        }
      ]
    },
    "remarks" :
    [
      {
        "description" :
        [
          "She sells sea shells down by the sea shore.",
          "Originally written by Terry Sullivan."
        ]
      }
    ],
    "links" :
    [
      {
        "value": "https://example.net/domain/0.2.192.in-addr.arpa",
        "rel" : "self",
        "href" : "https://example.net/domain/0.2.192.in-addr.arpa",
        "type" : "application/rdap+json"

      }
    ],
    "events" :
    [
      {
        "eventAction" : "registration",
        "eventDate" : "1990-12-31T23:59:59Z"
      },
      {
        "eventAction" : "last changed",
        "eventDate" : "1991-12-31T23:59:59Z",
        "eventActor" : "[email protected]"
      }
    ],
    "entities" :
    [
      {
        "objectClassName" : "entity",
        "handle" : "XXXX",
        "vcardArray":[
          "vcard",
          [
            ["version", {}, "text", "4.0"],
            ["fn", {}, "text", "Joe User"],
            ["kind", {}, "text", "individual"],
            ["lang", {
              "pref":"1"
            }, "language-tag", "fr"],
            ["lang", {
              "pref":"2"
            }, "language-tag", "en"],
            ["org", {
              "type":"work"
            }, "text", "Example"],
            ["title", {}, "text", "Research Scientist"],
            ["role", {}, "text", "Project Lead"],
            ["adr",
              { "type":"work" },
              "text",
              [
                "",
                "Suite 1234",
                "4321 Rue Somewhere",
                "Quebec",
                "QC",
                "G1V 2M2",
                "Canada"
              ]

            ],
            ["tel",
              { "type":["work", "voice"], "pref":"1" },
              "uri", "tel:+1-555-555-1234;ext=102"
            ],
            ["email",
              { "type":"work" },
              "text", "[email protected]"
            ]
          ]
        ],
        "roles" : [ "registrant" ],
        "remarks" :
        [
          {
            "description" :
            [
              "She sells sea shells down by the sea shore.",
              "Originally written by Terry Sullivan."
            ]
          }
        ],
        "links" :
        [
          {
            "value": "https://example.net/entity/XXXX",
            "rel" : "self",
            "href" : "https://example.net/entity/XXXX",
            "type" : "application/rdap+json"
          }
        ],
        "events" :
        [
          {
            "eventAction" : "registration",
            "eventDate" : "1990-12-31T23:59:59Z"
          },
          {
            "eventAction" : "last changed",
            "eventDate" : "1991-12-31T23:59:59Z",
            "eventActor" : "[email protected]"
          }
        ]
      }
    ],
    "network" :
    {
      "objectClassName" : "ip network",
      "handle" : "XXXX-RIR",
      "startAddress" : "192.0.2.0",
      "endAddress" : "192.0.2.255",
      "ipVersion" : "v4",
      "name": "NET-RTR-1",
      "type" : "DIRECT ALLOCATION",
      "country" : "AU",
      "parentHandle" : "YYYY-RIR",
      "status" : [ "active" ]
    }
  }

                                Figure 23

  The following is an example of a JSON domain object representing a
  forward DNS delegation point that might be served by a DNR.  Note
  that the secureDNS keyData publicKey value has been modified to fit
  on a single line.

  {
    "objectClassName" : "domain",
    "handle" : "XXXX",
    "ldhName" : "xn--fo-5ja.example",
    "unicodeName" : "fóo.example",
    "variants" :
    [
      {
        "relation" : [ "registered", "conjoined" ],
        "variantNames" :
        [
          {
            "ldhName" : "xn--fo-cka.example",
            "unicodeName" : "fõo.example"
          },
          {
            "ldhName" : "xn--fo-fka.example",
            "unicodeName" : "föo.example"
          }
        ]
      },
      {
        "relation" : [ "unregistered", "registration restricted" ],
        "idnTable": ".EXAMPLE Swedish",
        "variantNames" :
        [
          {
            "ldhName": "xn--fo-8ja.example",
            "unicodeName" : "fôo.example"
          }
        ]

      }
    ],
    "status" : [ "locked", "transfer prohibited" ],
    "publicIds":[
      {
        "type":"ENS_Auth ID",
        "identifier":"1234567890"
      }
    ],
    "nameservers" :
    [
      {
        "objectClassName" : "nameserver",
        "handle" : "XXXX",
        "ldhName" : "ns1.example.com",
        "status" : [ "active" ],
        "ipAddresses" :
        {
          "v6": [ "2001:db8::123", "2001:db8::124" ],
          "v4": [ "192.0.2.1", "192.0.2.2" ]
        },
        "remarks" :
        [
          {
            "description" :
            [
              "She sells sea shells down by the sea shore.",
              "Originally written by Terry Sullivan."
            ]
          }
        ],
        "links" :
        [
          {
            "value" : "https://example.net/nameserver/ns1.example.com",
            "rel" : "self",
            "href" : "https://example.net/nameserver/ns1.example.com",
            "type" : "application/rdap+json"
          }
        ],
        "events" :
        [
          {
            "eventAction" : "registration",
            "eventDate" : "1990-12-31T23:59:59Z"
          },
          {
            "eventAction" : "last changed",
            "eventDate" : "1991-12-31T23:59:59Z"
          }
        ]
      },
      {
        "objectClassName" : "nameserver",
        "handle" : "XXXX",
        "ldhName" : "ns2.example.com",
        "status" : [ "active" ],
        "ipAddresses" :
        {
          "v6" : [ "2001:db8::125", "2001:db8::126" ],
          "v4" : [ "192.0.2.3", "192.0.2.4" ]
        },
        "remarks" :
        [
          {
            "description" :
            [
              "She sells sea shells down by the sea shore.",
              "Originally written by Terry Sullivan."
            ]
          }
        ],
        "links" :
        [
          {
            "value" : "https://example.net/nameserver/ns2.example.com",
            "rel" : "self",
            "href" : "https://example.net/nameserver/ns2.example.com",
            "type" : "application/rdap+json"
          }
        ],
        "events" :
        [
          {
            "eventAction" : "registration",
            "eventDate" : "1990-12-31T23:59:59Z"
          },
          {
            "eventAction" : "last changed",
            "eventDate" : "1991-12-31T23:59:59Z"
          }
        ]
      }
    ],
    "secureDNS":
    {

       "zoneSigned": true,
       "delegationSigned": true,
       "maxSigLife": 604800,
       "keyData":
       [
         {
           "flags": 257,
           "protocol": 3,
           "algorithm": 8,
           "publicKey": "AwEAAa6eDzronzjEDbT...Jg1M5N rBSPkuXpdFE=",
           "events":
           [
             {
               "eventAction": "last changed",
               "eventDate": "2012-07-23T05:15:47Z"
             }
           ]
         }
       ]
    },
    "remarks" :
    [
      {
        "description" :
        [
          "She sells sea shells down by the sea shore.",
          "Originally written by Terry Sullivan."
        ]
      }
    ],
    "links" :
    [
      {
        "value": "https://example.net/domain/xn--fo-5ja.example",
        "rel" : "self",
        "href" : "https://example.net/domain/xn--fo-5ja.example",
        "type" : "application/rdap+json"
      }
    ],
    "port43" : "whois.example.net",
    "events" :
    [
      {
        "eventAction" : "registration",
        "eventDate" : "1990-12-31T23:59:59Z"
      },
      {
        "eventAction" : "last changed",
        "eventDate" : "1991-12-31T23:59:59Z",
        "eventActor" : "[email protected]"
      },
      {
        "eventAction" : "transfer",
        "eventDate" : "1991-12-31T23:59:59Z",
        "eventActor" : "[email protected]"
      },
      {
        "eventAction" : "expiration",
        "eventDate" : "2016-12-31T23:59:59Z",
        "eventActor" : "[email protected]"
      }
    ],
    "entities" :
    [
      {
        "objectClassName" : "entity",
        "handle" : "XXXX",
        "vcardArray":[
          "vcard",
          [
            ["version", {}, "text", "4.0"],
            ["fn", {}, "text", "Joe User"],
            ["kind", {}, "text", "individual"],
            ["lang", {
              "pref":"1"
            }, "language-tag", "fr"],
            ["lang", {
              "pref":"2"
            }, "language-tag", "en"],
            ["org", {
              "type":"work"
            }, "text", "Example"],
            ["title", {}, "text", "Research Scientist"],
            ["role", {}, "text", "Project Lead"],
            ["adr",
              { "type":"work" },
              "text",
              [
                "",
                "Suite 1234",
                "4321 Rue Somewhere",
                "Quebec",
                "QC",
                "G1V 2M2",
                "Canada"
              ]

            ],
            ["tel",
              { "type":["work", "voice"], "pref":"1" },
              "uri", "tel:+1-555-555-1234;ext=102"
            ],
            ["email",
              { "type":"work" },
              "text", "[email protected]"
            ]
          ]
        ],
        "status" : [ "validated", "locked" ],
        "roles" : [ "registrant" ],
        "remarks" :
        [
          {
            "description" :
            [
              "She sells sea shells down by the sea shore.",
              "Originally written by Terry Sullivan."
            ]
          }
        ],
        "links" :
        [
          {
            "value" : "https://example.net/entity/XXXX",
            "rel" : "self",
            "href" : "https://example.net/entity/XXXX",
            "type" : "application/rdap+json"
          }
        ],
        "events" :
        [
          {
            "eventAction" : "registration",
            "eventDate" : "1990-12-31T23:59:59Z"
          },
          {
            "eventAction" : "last changed",
            "eventDate" : "1991-12-31T23:59:59Z"
          }
        ]
      }
    ]
  }

                                Figure 24

5.4.  The IP Network Object Class

  The IP network object class models IP network registrations found in
  RIRs and is the expected response for the "/ip" query as defined by
  [RFC9082].  There is no equivalent object class for DNRs.  The high-
  level structure of the IP network object class consists of
  information about the network registration and entities related to
  the IP network (e.g., registrant information, contacts, etc.).

  The following is an elided example of the IP network object type
  showing the high-level structure:

  {
    "objectClassName" : "ip network",
    "handle" : "XXX",
    ...
    "entities" :
    [
      ...
    ]
  }

                                Figure 25

  The following is an example of the JSON object for the network
  registration information.

  {
    "objectClassName" : "ip network",
    "handle" : "XXXX-RIR",
    "startAddress" : "2001:db8::",
    "endAddress" : "2001:db8:0:ffff:ffff:ffff:ffff:ffff",
    "ipVersion" : "v6",
    "name": "NET-RTR-1",
    "type" : "DIRECT ALLOCATION",
    "country" : "AU",
    "parentHandle" : "YYYY-RIR",
    "status" : [ "active" ],
    "remarks" :
    [
      {
        "description" :
        [
          "She sells sea shells down by the sea shore.",
          "Originally written by Terry Sullivan."
        ]
      }
    ],
    "links" :
    [
      {
        "value" : "https://example.net/ip/2001:db8::/48",
        "rel" : "self",
        "href" : "https://example.net/ip/2001:db8::/48",
        "type" : "application/rdap+json"
      },
      {
        "value" : "https://example.net/ip/2001:db8::/48",
        "rel" : "up",
        "href" : "https://example.net/ip/2001:db8::/32",
        "type" : "application/rdap+json"
      }
    ],
    "events" :
    [
      {
        "eventAction" : "registration",
        "eventDate" : "1990-12-31T23:59:59Z"
      },
      {
        "eventAction" : "last changed",
        "eventDate" : "1991-12-31T23:59:59Z"
      }
    ],
    "entities" :
    [
      {
        "objectClassName" : "entity",
        "handle" : "XXXX",
        "vcardArray":[
          "vcard",
          [
            ["version", {}, "text", "4.0"],
            ["fn", {}, "text", "Joe User"],
            ["kind", {}, "text", "individual"],
            ["lang", {
              "pref":"1"
            }, "language-tag", "fr"],
            ["lang", {
              "pref":"2"
            }, "language-tag", "en"],
            ["org", {
              "type":"work"
            }, "text", "Example"],
            ["title", {}, "text", "Research Scientist"],
            ["role", {}, "text", "Project Lead"],
            ["adr",
              { "type":"work" },
              "text",
              [
                "",
                "Suite 1234",
                "4321 Rue Somewhere",
                "Quebec",
                "QC",
                "G1V 2M2",
                "Canada"
              ]
            ],
            ["tel",
              { "type":["work", "voice"], "pref":"1" },
              "uri", "tel:+1-555-555-1234;ext=102"
            ],
            ["email",
              { "type":"work" },
              "text", "[email protected]"
            ]
          ]
        ],
        "roles" : [ "registrant" ],
        "remarks" :
        [
          {
            "description" :
            [
              "She sells sea shells down by the sea shore.",
              "Originally written by Terry Sullivan."
            ]
          }
        ],
        "links" :
        [
          {
            "value" : "https://example.net/entity/xxxx",
            "rel" : "self",
            "href" : "https://example.net/entity/xxxx",
            "type" : "application/rdap+json"
          }
        ],
        "events" :
        [
          {
            "eventAction" : "registration",
            "eventDate" : "1990-12-31T23:59:59Z"

          },
          {
            "eventAction" : "last changed",
            "eventDate" : "1991-12-31T23:59:59Z"
          }
        ]
      }
    ]
  }

                                Figure 26

  The IP network object class can contain the following members:

  *  objectClassName -- the string "ip network"

  *  handle -- a string representing the RIR-unique identifier of the
     network registration

  *  startAddress -- a string representing the starting IP address of
     the network, either IPv4 or IPv6

  *  endAddress -- a string representing the ending IP address of the
     network, either IPv4 or IPv6

  *  ipVersion -- a string signifying the IP protocol version of the
     network: "v4" signifies an IPv4 network, and "v6" signifies an
     IPv6 network

  *  name -- a string representing an identifier assigned to the
     network registration by the registration holder

  *  type -- a string containing an RIR-specific classification of the
     network per that RIR's registration model

  *  country -- a string containing the two-character country code of
     the network

  *  parentHandle -- a string containing an RIR-unique identifier of
     the parent network of this network registration

  *  status -- an array of strings indicating the state of the IP
     network as defined by Section 4.6

  *  entities -- an array of entity objects as defined by Section 5.1

  *  remarks -- see Section 4.3

  *  links -- see Section 4.2

  *  port43 -- see Section 4.7

  *  events -- see Section 4.5

5.5.  The Autonomous System Number Object Class

  The Autonomous System number (autnum) object class models Autonomous
  System number registrations found in RIRs and represents the expected
  response to an "/autnum" query as defined by [RFC9082].  There is no
  equivalent object class for DNRs.  The high-level structure of the
  autnum object class consists of information about the Autonomous
  System number registration and entities related to the autnum
  registration (e.g., registrant information, contacts, etc.) and is
  similar to the IP network object class.

  The following is an example of a JSON object representing an autnum.

  {
    "objectClassName" : "autnum",
    "handle" : "XXXX-RIR",
    "startAutnum" : 65536,
    "endAutnum" : 65541,
    "name": "AS-RTR-1",
    "type" : "DIRECT ALLOCATION",
    "status" : [ "active" ],
    "country": "AU",
    "remarks" :
    [
      {
        "description" :
        [
          "She sells sea shells down by the sea shore.",
          "Originally written by Terry Sullivan."
        ]
      }
    ],
    "links" :
    [
      {
        "value" : "https://example.net/autnum/65537",
        "rel" : "self",
        "href" : "https://example.net/autnum/65537",
        "type" : "application/rdap+json"
      }
    ],
    "events" :

    [
      {
        "eventAction" : "registration",
        "eventDate" : "1990-12-31T23:59:59Z"
      },
      {
        "eventAction" : "last changed",
        "eventDate" : "1991-12-31T23:59:59Z"
      }
    ],
    "entities" :
    [
      {
        "objectClassName" : "entity",
        "handle" : "XXXX",
        "vcardArray":[
          "vcard",
          [
            ["version", {}, "text", "4.0"],
            ["fn", {}, "text", "Joe User"],
            ["kind", {}, "text", "individual"],
            ["lang", {
              "pref":"1"
            }, "language-tag", "fr"],
            ["lang", {
              "pref":"2"
            }, "language-tag", "en"],
            ["org", {
              "type":"work"
            }, "text", "Example"],
            ["title", {}, "text", "Research Scientist"],
            ["role", {}, "text", "Project Lead"],
            ["adr",
              { "type":"work" },
              "text",
              [
                "",
                "Suite 1234",
                "4321 Rue Somewhere",
                "Quebec",
                "QC",
                "G1V 2M2",
                "Canada"
              ]
            ],
            ["tel",
              { "type":["work", "voice"], "pref":"1" },
              "uri", "tel:+1-555-555-1234;ext=102"
            ],
            ["email",
              { "type":"work" },
              "text", "[email protected]"
            ]
          ]
        ],
        "roles" : [ "registrant" ],
        "remarks" :
        [
          {
            "description" :
            [
              "She sells sea shells down by the sea shore.",
              "Originally written by Terry Sullivan."
            ]
          }
        ],
        "links" :
        [
          {
            "value" : "https://example.net/entity/XXXX",
            "rel" : "self",
            "href" : "https://example.net/entity/XXXX",
            "type" : "application/rdap+json"
          }
        ],
        "events" :
        [
          {
            "eventAction" : "registration",
            "eventDate" : "1990-12-31T23:59:59Z"
          },
          {
            "eventAction" : "last changed",
            "eventDate" : "1991-12-31T23:59:59Z"
          }
        ]
      }
    ]
  }

                                Figure 27

  The Autonomous System number object class can contain the following
  members:

  *  objectClassName -- the string "autnum"

  *  handle -- a string representing the RIR-unique identifier of the
     autnum registration

  *  startAutnum -- an unsigned 32-bit integer representing the
     starting number [RFC5396] in the block of Autonomous System
     numbers

  *  endAutnum -- an unsigned 32-bit integer representing the ending
     number [RFC5396] in the block of Autonomous System numbers

  *  name -- a string representing an identifier assigned to the autnum
     registration by the registration holder

  *  type -- a string containing an RIR-specific classification of the
     autnum per that RIR's registration model

  *  status -- an array of strings indicating the state of the autnum
     as defined by Section 4.6

  *  country -- a string containing the two-character country code of
     the autnum

  *  entities -- an array of entity objects as defined by Section 5.1

  *  remarks -- see Section 4.3

  *  links -- see Section 4.2

  *  port43 -- see Section 4.7

  *  events -- see Section 4.5

6.  Error Response Body

  Some non-answer responses MAY return entity bodies with information
  that could be more descriptive.

  The basic structure of that response is an object class containing a
  REQUIRED error code number (corresponding to the HTTP response code)
  followed by an OPTIONAL string named "title" and an OPTIONAL array of
  strings named "description".

  This is an example of the common response body.

  {
    "errorCode": 418,
    "title": "Your Beverage Choice is Not Available",
    "description":
    [
      "I know coffee has more ummppphhh.",
      "Sorry, dude!"
    ]
  }

                                Figure 28

  This is an example of the common response body with an
  rdapConformance and notices data structures:

  {
    "rdapConformance" :
    [
      "rdap_level_0"
    ],
    "notices" :
    [
      {
        "title" : "Beverage Policy",
        "description" :
        [
          "Beverages with caffeine for keeping horses awake."
        ],
        "links" :
        [
          {
            "value" : "https://example.net/ip/192.0.2.0/24",
            "rel" : "alternate",
            "type" : "text/html",
            "href" : "https://www.example.com/redaction_policy.html"
          }
        ]
      }
    ],
    "lang" : "en",
    "errorCode": 418,
    "title": "Your beverage choice is not available",
    "description":
    [
      "I know coffee has more ummppphhh.",
      "Sorry, dude!"
    ]
  }

                                Figure 29

7.  Responding to Help Queries

  The appropriate response to /help queries as defined by [RFC9082] is
  to use the notices structure as defined in Section 4.3.

  This is an example of a response to a /help query including the
  rdapConformance data structure.

  {
    "rdapConformance" :
    [
      "rdap_level_0"
    ],
    "notices" :
    [
      {
        "title" : "Authentication Policy",
        "description" :
        [
          "Access to sensitive data for users with proper credentials."
        ],
        "links" :
        [
          {
            "value" : "https://example.net/help",
            "rel" : "alternate",
            "type" : "text/html",
            "href" : "https://www.example.com/auth_policy.html"
          }
        ]
      }
    ]
  }

                                Figure 30

8.  Responding To Searches

  [RFC9082] specifies three types of searches: domains, nameservers,
  and entities.  Responses to these searches take the form of an array
  of object instances where each instance is an appropriate object
  class for the search (i.e., a search for /domains yields an array of
  domain object instances).  These arrays are contained within the
  response object.

  The names of the arrays are as follows:

  *  for /domains searches, the array is "domainSearchResults"

  *  for /nameservers searches, the array is "nameserverSearchResults"

  *  for /entities searches, the array is "entitySearchResults"

  The following is an elided example of a response to a /domains
  search.

  {
    "rdapConformance" :
    [
      "rdap_level_0"
    ],
    ...
    "domainSearchResults" :
    [
      {
        "objectClassName" : "domain",
        "handle" : "1-XXXX",
        "ldhName" : "1.example.com",
        ...
      },
      {
        "objectClassName" : "domain",
        "handle" : "2-XXXX",
        "ldhName" : "2.example.com",
        ...
      }
    ]
  }

                                Figure 31

9.  Indicating Truncated Responses

  In cases where the data of a response needs to be limited or parts of
  the data need to be omitted, the response is considered "truncated".
  A truncated response is still valid JSON, but some of the results in
  a search set or some of the data in an object are not provided by the
  server.  A server may indicate this by including a typed notice in
  the response object.

  The following is an elided example of a search response that has been
  truncated.

  {
    "rdapConformance" :
    [
      "rdap_level_0"
    ],
    "notices" :
    [
      {
        "title" : "Search Policy",
        "type" : "result set truncated due to authorization",
        "description" :
        [
          "Search results are limited to 25 per day per querying IP."
        ],
        "links" :
        [
          {
            "value" : "https://example.net/help",
            "rel" : "alternate",
            "type" : "text/html",
            "href" : "https://www.example.com/search_policy.html"
          }
        ]
      }
    ],
    "domainSearchResults" :
    [
      ...
    ]
  }

                                Figure 32

  A similar technique can be used with a typed remark where a single
  object has been returned and data in that object has been truncated.
  Such an example might be an entity object with only a partial set of
  the IP networks associated with it.

  The following is an elided example of an entity truncated data.

  {
    "objectClassName" : "entity",
    "handle" : "ANENTITY",
    "roles" : [ "registrant" ],
    ...
    "entities" :
    [
      {
        "objectClassName" : "entity",
        "handle": "ANEMBEDDEDENTITY",
        "roles" : [ "technical" ],
        ...
      },
      ...
    ],
    "networks" :
    [
      ...
    ],
    ...
    "remarks" :
    [
      {
        "title" : "Data Policy",
        "type" : "object truncated due to unexplainable reason",
        "description" :
        [
          "Some of the data in this object has been removed."
        ],
        "links" :
        [
          {
            "value" : "https://example.net/help",
            "rel" : "alternate",
            "type" : "text/html",
            "href" : "https://www.example.com/data_policy.html"
          }
        ]
      }
    ]
  }

                                Figure 33

10.  IANA Considerations

  IANA has updated the description of the "transfer" event action as
  described in Section 10.2.3.

10.1.  RDAP JSON Media Type Registration

  IANA has updated the media type registration as described below.

  This specification registers the "application/rdap+json" media type.

  Type name:  application

  Subtype name:  rdap+json

  Required parameters:  n/a

  Encoding considerations:  See Section 3.1 of [RFC6839].

  Security considerations:  The media represented by this identifier
     does not have security considerations beyond that found in
     Section 12 of [RFC8259].

  Interoperability considerations:  There are no known interoperability
     problems regarding this media format.

  Published specification:  RFC 9083

  Applications that use this media type:  Implementations of the
     Registration Data Access Protocol (RDAP).

  Additional information:  This media type is a product of the IETF
     REGEXT Working Group.  The REGEXT charter, information on the
     REGEXT mailing list, and other documents produced by the REGEXT
     Working Group can be found at https://datatracker.ietf.org/wg/
     regext/.

  Person & email address to contact for further information:
     IESG <[email protected]>

  Intended usage:  COMMON

  Restrictions on usage:  none

  Author:  Andy Newton

  Change controller:  IETF

  Provisional Registration:  No

10.2.  JSON Values Registry

  IANA has created a category in the protocol registries labeled
  "Registration Data Access Protocol (RDAP)", and within that category,
  IANA has established a URL-referenceable, stand-alone registry
  labeled "RDAP JSON Values".  This new registry is for use in the
  notices and remarks (Section 4.3), status (Section 4.6), role
  (Section 5.1), event action (Section 4.5), and domain variant
  relation (Section 5.3) fields specified in RDAP.

  Each entry in the registry contains the following fields:

  1.  Value -- the string value being registered.

  2.  Type -- the type of value being registered.  It should be one of
      the following:

      *  "notice or remark type" -- denotes a type of notice or remark.

      *  "status" -- denotes a value for the "status" object member as
         defined by Section 4.6.

      *  "role" -- denotes a value for the "role" array as defined in
         Section 5.1.

      *  "event action" -- denotes a value for an event action as
         defined in Section 4.5.

      *  "domain variant relation" -- denotes a relationship between a
         domain and a domain variant as defined in Section 5.3.

  3.  Description -- a one- or two-sentence description regarding the
      meaning of the value, how it might be used, and/or how it should
      be interpreted by clients.

  4.  Registrant Name -- the name of the person registering the value.

  5.  Registrant Contact Information -- an email address, postal
      address, or some other information to be used to contact the
      registrant.

  This registry is operated under the "Expert Review" policy defined in
  [RFC8126].

  Review of registrations into this registry by the designated
  expert(s) should be narrowly judged on the following criteria:

  1.  Values in need of being placed into multiple types must be
      assigned a separate registration for each type.

  2.  Values must be strings.  They should be multiple words separated
      by single space characters.  Every character should be
      lowercased.  If possible, every word should be given in English
      and each character should be US-ASCII.

  3.  Registrations should not duplicate the meaning of any existing
      registration.  That is, if a request for a registration is
      significantly similar in nature to an existing registration, the
      request should be denied.  For example, the terms "maintainer"
      and "registrant" are significantly similar in nature as they both
      denote a holder of a domain name or Internet number resource.  In
      cases where it may be reasonably argued that machine
      interpretation of two similar values may alter the operation of
      client software, designated experts should not judge the values
      to be of significant similarity.

  4.  Registrations should be relevant to the common usages of RDAP.
      Designated experts may rely upon the serving of the value by a
      DNR or RIR to make this determination.

  The following sections provide initial registrations into this
  registry.

10.2.1.  Notice and Remark Types

  The following values have been registered in the "RDAP JSON Values"
  registry:

  Value:  result set truncated due to authorization
  Type:  notice and remark type
  Description:  The list of results does not contain all results due to
     lack of authorization.  This may indicate to some clients that
     proper authorization will yield a longer result set.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  result set truncated due to excessive load
  Type:  notice and remark type
  Description:  The list of results does not contain all results due to
     an excessively heavy load on the server.  This may indicate to
     some clients that requerying at a later time will yield a longer
     result set.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  result set truncated due to unexplainable reasons
  Type:  notice and remark type
  Description:  The list of results does not contain all results for an
     unexplainable reason.  This may indicate to some clients that
     requerying for any reason will not yield a longer result set.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  object truncated due to authorization
  Type:  notice and remark type
  Description:  The object does not contain all data due to lack of
     authorization.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  object truncated due to excessive load
  Type:  notice and remark type
  Description:  The object does not contain all data due to an
     excessively heavy load on the server.  This may indicate to some
     clients that requerying at a later time will yield all data of the
     object.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  object truncated due to unexplainable reasons
  Type:  notice and remark type
  Description:  The object does not contain all data for an
     unexplainable reason.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

10.2.2.  Status

  The following values have been registered in the "RDAP JSON Values"
  registry:

  Value:  validated
  Type:  status
  Description:  Signifies that the data of the object instance has been
     found to be accurate.  This type of status is usually found on
     entity object instances to note the validity of identifying
     contact information.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  renew prohibited
  Type:  status
  Description:  Renewal or reregistration of the object instance is
     forbidden.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  update prohibited
  Type:  status
  Description:  Updates to the object instance are forbidden.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  transfer prohibited
  Type:  status
  Description:  Transfers of the registration from one registrar to
     another are forbidden.  This type of status normally applies to
     DNR domain names.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  delete prohibited
  Type:  status
  Description:  Deletion of the registration of the object instance is
     forbidden.  This type of status normally applies to DNR domain
     names.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  proxy
  Type:  status
  Description:  The registration of the object instance has been
     performed by a third party.  This is most commonly applied to
     entities.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  private
  Type:  status
  Description:  The information of the object instance is not
     designated for public consumption.  This is most commonly applied
     to entities.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  removed
  Type:  status
  Description:  Some of the information of the object instance has not
     been made available and has been removed.  This is most commonly
     applied to entities.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  obscured
  Type:  status
  Description:  Some of the information of the object instance has been
     altered for the purposes of not readily revealing the actual
     information of the object instance.  This is most commonly applied
     to entities.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  associated
  Type:  status
  Description:  The object instance is associated with other object
     instances in the registry.  This is most commonly used to signify
     that a nameserver is associated with a domain or that an entity is
     associated with a network resource or domain.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  active
  Type:  status
  Description:  The object instance is in use.  For domain names, it
     signifies that the domain name is published in DNS.  For network
     and autnum registrations, it signifies that they are allocated or
     assigned for use in operational networks.  This maps to the "OK"
     status of the Extensible Provisioning Protocol (EPP) [RFC5730].
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  inactive
  Type:  status
  Description:  The object instance is not in use.  See "active".
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  locked
  Type:  status
  Description:  Changes to the object instance cannot be made,
     including the association of other object instances.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  pending create
  Type:  status
  Description:  A request has been received for the creation of the
     object instance, but this action is not yet complete.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  pending renew
  Type:  status
  Description:  A request has been received for the renewal of the
     object instance, but this action is not yet complete.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  pending transfer
  Type:  status
  Description:  A request has been received for the transfer of the
     object instance, but this action is not yet complete.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  pending update
  Type:  status
  Description:  A request has been received for the update or
     modification of the object instance, but this action is not yet
     complete.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  pending delete
  Type:  status
  Description:  A request has been received for the deletion or removal
     of the object instance, but this action is not yet complete.  For
     domains, this might mean that the name is no longer published in
     DNS but has not yet been purged from the registry database.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

10.2.3.  Event Actions

  The following values have been registered in the "RDAP JSON Values"
  registry:

  Value:  registration
  Type:  event action
  Description:  The object instance was initially registered.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  reregistration
  Type:  event action
  Description:  The object instance was registered subsequently to
     initial registration.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  last changed
  Type:  event action
  Description:  An action noting when the information in the object
     instance was last changed.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  expiration
  Type:  event action
  Description:  The object instance has been removed or will be removed
     at a predetermined date and time from the registry.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  deletion
  Type:  event action
  Description:  The object instance was removed from the registry at a
     point in time that was not predetermined.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  reinstantiation
  Type:  event action
  Description:  The object instance was reregistered after having been
     removed from the registry.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  transfer
  Type:  event action
  Description:  The object instance was transferred from one registrar
     to another.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  locked
  Type:  event action
  Description:  The object instance was locked (see the "locked"
     status).
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  unlocked
  Type:  event action
  Description:  The object instance was unlocked (see the "locked"
     status).
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

10.2.4.  Roles

  The following values have been registered in the "RDAP JSON Values"
  registry:

  Value:  registrant
  Type:  role
  Description:  The entity object instance is the registrant of the
     registration.  In some registries, this is known as a maintainer.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  technical
  Type:  role
  Description:  The entity object instance is a technical contact for
     the registration.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  administrative
  Type:  role
  Description:  The entity object instance is an administrative contact
     for the registration.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  abuse
  Type:  role
  Description:  The entity object instance handles network abuse issues
     on behalf of the registrant of the registration.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  billing
  Type:  role
  Description:  The entity object instance handles payment and billing
     issues on behalf of the registrant of the registration.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  registrar
  Type:  role
  Description:  The entity object instance represents the authority
     responsible for the registration in the registry.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  reseller
  Type:  role
  Description:  The entity object instance represents a third party
     through which the registration was conducted (i.e., not the
     registry or registrar).
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  sponsor
  Type:  role
  Description:  The entity object instance represents a domain policy
     sponsor, such as an ICANN-approved sponsor.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  proxy
  Type:  role
  Description:  The entity object instance represents a proxy for
     another entity object, such as a registrant.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  notifications
  Type:  role
  Description:  An entity object instance designated to receive
     notifications about association object instances.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  noc
  Type:  role
  Description:  The entity object instance handles communications
     related to a network operations center (NOC).
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

10.2.5.  Variant Relations

  The following values have been registered in the "RDAP JSON Values"
  registry:

  Value:  registered
  Type:  domain variant relation
  Description:  The variant names are registered in the registry.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  unregistered
  Type:  domain variant relation
  Description:  The variant names are not found in the registry.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  registration restricted
  Type:  domain variant relation
  Description:  Registration of the variant names is restricted to
     certain parties or within certain rules.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  open registration
  Type:  domain variant relation
  Description:  Registration of the variant names is available to
     generally qualified registrants.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

  Value:  conjoined
  Type:  domain variant relation
  Description:  Registration of the variant names occurs automatically
     with the registration of the containing domain registration.
  Registrant Name:  IESG
  Registrant Contact Information:  [email protected]

11.  Security Considerations

  This specification models information serialized in JSON format.  As
  JSON is a subset of JavaScript, implementations are advised to follow
  the security considerations outlined in Section 12 of [RFC8259] to
  prevent code injection.

  Though not specific to JSON, RDAP implementers should be aware of the
  security considerations specified in [RFC7480] and the security
  requirements and considerations in [RFC7481].

  RDAP responses allow for retrieval of DNSSEC (key) related
  information, but the RRSIG DS from the parent zone is not conveyed
  alongside it.  This means that the DNSSEC keys retrieved by RDAP are
  disconnected from their containing PKI, and as such are not generally
  expected to be trusted without additional information.  In
  particular, the HTTPS channel protecting the RDAP connection is not
  expected to be authorized to certify the validity of the DNSSEC keys.

  Clients caching data, especially clients using RDAP-specific caches
  (instead of HTTP-layer caches), should have safeguards to prevent
  cache poisoning.  See Section 5 for advice on using the self links
  for caching.

  Finally, service operators should be aware of the privacy mechanisms
  noted in Section 13.

12.  Internationalization Considerations

12.1.  Character Encoding

  The default text encoding for JSON responses in RDAP is UTF-8
  [RFC3629], and all servers and clients MUST support UTF-8.

12.2.  URIs and IRIs

  [RFC7480] defines the use of URIs and IRIs in RDAP.

12.3.  Language Tags

  Section 4.4 defines the use of language tags in the JSON responses
  defined in this document.

12.4.  Internationalized Domain Names

  IDNs are denoted in this specification by the separation of DNS names
  in LDH form and Unicode form (see Section 3).  Representation of IDNs
  in registries is described by the "variants" object in Section 5.3
  and the suggested values listed in Section 10.2.5.

13.  Privacy Considerations

  This specification suggests status values to denote contact and
  registrant information that has been marked as private and/or has
  been removed or obscured.  See Section 10.2.2 for the complete list
  of status values.  A few of the status values indicate that there are
  privacy concerns associated with the object instance.  The following
  status codes SHOULD be used to describe data elements of a response
  when appropriate:

  *  private -- The object is not be shared in query responses, unless
     the user is authorized to view this information.

  *  removed -- Data elements within the object have been collected but
     have been omitted from the response.  This option can be used to
     prevent unauthorized access to associated object instances without
     the need to mark them as private.

  *  obscured -- Data elements within the object have been collected,
     but the response value has been altered so that values are not
     easily discernible.  A value changed from "1212" to "XXXX" is an
     example of obscured data.  This option may reveal privacy
     sensitive information and should only be used when data
     sensitivity does not require a more protective option like
     "private" or "removed".

  See Appendix A.1 for an example of applying those values to contacts
  and registrants.

14.  References

14.1.  Normative References

  [ISO.3166.2020]
             International Organization for Standardization, "Codes for
             the representation of names of countries and their
             subdivisions", Fourth edition, ISO Standard 3166, August
             2020.

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119,
             DOI 10.17487/RFC2119, March 1997,
             <https://www.rfc-editor.org/info/rfc2119>.

  [RFC3339]  Klyne, G. and C. Newman, "Date and Time on the Internet:
             Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
             <https://www.rfc-editor.org/info/rfc3339>.

  [RFC3629]  Yergeau, F., "UTF-8, a transformation format of ISO
             10646", STD 63, RFC 3629, DOI 10.17487/RFC3629, November
             2003, <https://www.rfc-editor.org/info/rfc3629>.

  [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
             Resource Identifier (URI): Generic Syntax", STD 66,
             RFC 3986, DOI 10.17487/RFC3986, January 2005,
             <https://www.rfc-editor.org/info/rfc3986>.

  [RFC4034]  Arends, R., Austein, R., Larson, M., Massey, D., and S.
             Rose, "Resource Records for the DNS Security Extensions",
             RFC 4034, DOI 10.17487/RFC4034, March 2005,
             <https://www.rfc-editor.org/info/rfc4034>.

  [RFC5396]  Huston, G. and G. Michaelson, "Textual Representation of
             Autonomous System (AS) Numbers", RFC 5396,
             DOI 10.17487/RFC5396, December 2008,
             <https://www.rfc-editor.org/info/rfc5396>.

  [RFC5646]  Phillips, A., Ed. and M. Davis, Ed., "Tags for Identifying
             Languages", BCP 47, RFC 5646, DOI 10.17487/RFC5646,
             September 2009, <https://www.rfc-editor.org/info/rfc5646>.

  [RFC5890]  Klensin, J., "Internationalized Domain Names for
             Applications (IDNA): Definitions and Document Framework",
             RFC 5890, DOI 10.17487/RFC5890, August 2010,
             <https://www.rfc-editor.org/info/rfc5890>.

  [RFC5952]  Kawamura, S. and M. Kawashima, "A Recommendation for IPv6
             Address Text Representation", RFC 5952,
             DOI 10.17487/RFC5952, August 2010,
             <https://www.rfc-editor.org/info/rfc5952>.

  [RFC7095]  Kewisch, P., "jCard: The JSON Format for vCard", RFC 7095,
             DOI 10.17487/RFC7095, January 2014,
             <https://www.rfc-editor.org/info/rfc7095>.

  [RFC7480]  Newton, A., Ellacott, B., and N. Kong, "HTTP Usage in the
             Registration Data Access Protocol (RDAP)", STD 95,
             RFC 7480, DOI 10.17487/RFC7480, March 2015,
             <https://www.rfc-editor.org/info/rfc7480>.

  [RFC7481]  Hollenbeck, S. and N. Kong, "Security Services for the
             Registration Data Access Protocol (RDAP)", STD 95,
             RFC 7481, DOI 10.17487/RFC7481, March 2015,
             <https://www.rfc-editor.org/info/rfc7481>.

  [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
             Writing an IANA Considerations Section in RFCs", BCP 26,
             RFC 8126, DOI 10.17487/RFC8126, June 2017,
             <https://www.rfc-editor.org/info/rfc8126>.

  [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
             2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
             May 2017, <https://www.rfc-editor.org/info/rfc8174>.

  [RFC8259]  Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
             Interchange Format", STD 90, RFC 8259,
             DOI 10.17487/RFC8259, December 2017,
             <https://www.rfc-editor.org/info/rfc8259>.

  [RFC8288]  Nottingham, M., "Web Linking", RFC 8288,
             DOI 10.17487/RFC8288, October 2017,
             <https://www.rfc-editor.org/info/rfc8288>.

  [RFC9082]  Hollenbeck, S. and A. Newton, "Registration Data Access
             Protocol (RDAP) Query Format", STD 95, RFC 9082,
             DOI 10.17487/RFC9082, June 2021,
             <https://www.rfc-editor.org/info/rfc9082>.

14.2.  Informative References

  [IANA_IDNTABLES]
             IANA, "Repository of IDN Practices",
             <https://www.iana.org/domains/idn-tables>.

  [JSON_ascendancy]
             MacVittie, L., "The Stealthy Ascendancy of JSON", April
             2011, <https://devcentral.f5.com/s/articles/the-stealthy-
             ascendancy-of-json>.

  [JSON_performance_study]
             Nurseitov, N., Paulson, M., Reynolds, R., and C. Izurieta,
             "Comparison of JSON and XML Data Interchange Formats: A
             Case Study", 2009,
             <https://www.cs.montana.edu/izurieta/pubs/caine2009.pdf>.

  [RFC3912]  Daigle, L., "WHOIS Protocol Specification", RFC 3912,
             DOI 10.17487/RFC3912, September 2004,
             <https://www.rfc-editor.org/info/rfc3912>.

  [RFC5730]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
             STD 69, RFC 5730, DOI 10.17487/RFC5730, August 2009,
             <https://www.rfc-editor.org/info/rfc5730>.

  [RFC5910]  Gould, J. and S. Hollenbeck, "Domain Name System (DNS)
             Security Extensions Mapping for the Extensible
             Provisioning Protocol (EPP)", RFC 5910,
             DOI 10.17487/RFC5910, May 2010,
             <https://www.rfc-editor.org/info/rfc5910>.

  [RFC6350]  Perreault, S., "vCard Format Specification", RFC 6350,
             DOI 10.17487/RFC6350, August 2011,
             <https://www.rfc-editor.org/info/rfc6350>.

  [RFC6839]  Hansen, T. and A. Melnikov, "Additional Media Type
             Structured Syntax Suffixes", RFC 6839,
             DOI 10.17487/RFC6839, January 2013,
             <https://www.rfc-editor.org/info/rfc6839>.

Appendix A.  Suggested Data Modeling with the Entity Object Class

A.1.  Registrants and Contacts

  This document does not provide specific object classes for
  registrants and contacts.  Instead, the entity object class may be
  used to represent a registrant or contact.  When the entity object is
  embedded inside a containing object such as a domain name or IP
  network, the "roles" string array can be used to signify the
  relationship.  It is recommended that the values from Section 10.2.4
  be used.

  The following is an example of an elided containing object with an
  embedded entity that is both a registrant and administrative contact:

  {
    ...
    "entities" :
    [
      {
        "objectClassName" : "entity",
        "handle" : "XXXX",
        "vcardArray":[
          "vcard",
          [
            ["version", {}, "text", "4.0"],
            ["fn", {}, "text", "Joe User"],
            ["kind", {}, "text", "individual"],
            ["lang", {
              "pref":"1"
            }, "language-tag", "fr"],
            ["lang", {
              "pref":"2"
            }, "language-tag", "en"],
            ["org", {
              "type":"work"
            }, "text", "Example"],
            ["title", {}, "text", "Research Scientist"],
            ["role", {}, "text", "Project Lead"],
            ["adr",
              { "type":"work" },
              "text",
              [
                "",
                "Suite 1234",
                "4321 Rue Somewhere",
                "Quebec",
                "QC",
                "G1V 2M2",
                "Canada"
              ]
            ],
            ["tel",
              { "type":["work", "voice"], "pref":"1" },
              "uri", "tel:+1-555-555-1234;ext=102"
            ],
            ["email",
              { "type":"work" },
              "text", "[email protected]"
            ]
          ]
        ],
        "roles" : [ "registrant", "administrative" ],
        "remarks" :
        [
          {
            "description" :
            [
              "She sells sea shells down by the sea shore.",
              "Originally written by Terry Sullivan."
            ]
          }
        ],
        "events" :
        [
          {
            "eventAction" : "registration",
            "eventDate" : "1990-12-31T23:59:59Z"
          },
          {
            "eventAction" : "last changed",
            "eventDate" : "1991-12-31T23:59:59Z"
          }
        ]
      }
    ]
  }

                                Figure 34

  In many use cases, it is necessary to hide or obscure the information
  of a registrant or contact due to policy or other operational
  matters.  Registries can denote these situations with "status" values
  (see Section 10.2.2).

  The following is an elided example of a registrant with information
  changed to reflect that of a third party.

  {
    ...
    "entities" :
    [
      {
        "objectClassName" : "entity",
        "handle" : "XXXX",
        ...
        "roles" : [ "registrant", "administrative" ],
        "status" : [ "proxy", "private", "obscured" ]
      }
    ]
  }

                                Figure 35

A.2.  Registrars

  This document does not provide a specific object class for
  registrars, but like registrants and contacts (see Appendix A.1), the
  "roles" string array maybe used.  Additionally, many registrars have
  publicly assigned identifiers.  The publicIds structure (Section 4.8)
  represents that information.

  The following is an example of an elided containing object with an
  embedded entity that is a registrar:

  {
    ...
    "entities":[
      {
        "objectClassName" : "entity",
        "handle":"XXXX",
        "vcardArray":[
          "vcard",
          [
            ["version", {}, "text", "4.0"],
            ["fn", {}, "text", "Joe's Fish, Chips, and Domains"],
            ["kind", {}, "text", "org"],
            ["lang", {
              "pref":"1"
            }, "language-tag", "fr"],
            ["lang", {
              "pref":"2"
            }, "language-tag", "en"],
            ["org", {
              "type":"work"
            }, "text", "Example"],
            ["adr",
              { "type":"work" },
              "text",
              [
                "",
                "Suite 1234",
                "4321 Rue Somewhere",
                "Quebec",
                "QC",
                "G1V 2M2",
                "Canada"
              ]
            ],
            ["tel",
              {
                "type":["work", "voice"],
                "pref":"1"
              },
              "uri", "tel:+1-555-555-1234;ext=102"
            ],
            ["email",
              { "type":"work" },
              "text", "[email protected]"
            ]
          ]
        ],
        "roles":[ "registrar" ],
        "publicIds":[
          {
            "type":"IANA Registrar ID",
            "identifier":"1"
          }
        ],
        "remarks":[
          {
            "description":[
              "She sells sea shells down by the sea shore.",
              "Originally written by Terry Sullivan."
            ]
          }
        ],
        "links":[
          {
            "value":"https://example.net/entity/XXXX",
            "rel":"alternate",
            "type":"text/html",
            "href":"https://www.example.com"
          }
        ]
      }
    ]
  }

                                Figure 36

Appendix B.  Modeling Events

  Events represent actions that have taken place against a registered
  object at a certain date and time.  Events have three properties: the
  action, the actor, and the date and time of the event (which is
  sometimes in the future).  In some cases, the identity of the actor
  is not captured.

  Events can be modeled in three ways:

  1.  events with no designated actor

  2.  events where the actor is only designated by an identifier

  3.  events where the actor can be modeled as an entity

  For the first use case, the events data structure (Section 4.5) is
  used without the "eventActor" object member.

  This is an example of an "events" array without the "eventActor".

  "events" :
  [
    {
      "eventAction" : "registration",
      "eventDate" : "1990-12-31T23:59:59Z"
    }
  ]

                                Figure 37

  For the second use case, the events data structure (Section 4.5) is
  used with the "eventActor" object member.

  This is an example of an "events" array with the "eventActor".

  "events" :
  [
    {
      "eventAction" : "registration",
      "eventActor" : "XYZ-NIC",
      "eventDate" : "1990-12-31T23:59:59Z"
    }
  ]

                                Figure 38

  For the third use case, the "asEventActor" array is used when an
  entity (Section 5.1) is embedded into another object class.  The
  "asEventActor" array follows the same structure as the "events" array
  but does not have "eventActor" attributes.

  The following is an elided example of a domain object with an entity
  as an event actor.

  {
    "objectClassName" : "domain",
    "handle" : "XXXX",
    "ldhName" : "foo.example",
    "status" : [ "locked", "transfer prohibited" ],
    ...
    "entities" :
    [
      {
        "handle" : "XXXX",
        ...
        "asEventActor" :
        [
          {
            "eventAction" : "last changed",
            "eventDate" : "1990-12-31T23:59:59Z"
          }
        ]
      }
    ]
  }

                                Figure 39

Appendix C.  Structured vs. Unstructured Addresses

  The entity (Section 5.1) object class uses jCard [RFC7095] to
  represent contact information, including postal addresses. jCard has
  the ability to represent multiple language preferences, multiple
  email address and phone numbers, and multiple postal addresses in
  both a structured and unstructured format.  This section describes
  the use of jCard for representing structured and unstructured
  addresses.

  The following is an example of a jCard.

  {
    "vcardArray":[
      "vcard",
      [
        ["version", {}, "text", "4.0"],
        ["fn", {}, "text", "Joe User"],
        ["n", {}, "text",
          ["User", "Joe", "", "", ["ing. jr", "M.Sc."]]
        ],
        ["kind", {}, "text", "individual"],
        ["lang", {
          "pref":"1"
        }, "language-tag", "fr"],
        ["lang", {
          "pref":"2"
        }, "language-tag", "en"],
        ["org", {
          "type":"work"
        }, "text", "Example"],
        ["title", {}, "text", "Research Scientist"],
        ["role", {}, "text", "Project Lead"],
        ["adr",
          { "type":"work" },
          "text",
          [
            "",
            "Suite 1234",
            "4321 Rue Somewhere",
            "Quebec",
            "QC",
            "G1V 2M2",
            "Canada"
          ]
        ],
        ["adr",
          {

            "type":"home",
            "label":"123 Maple Ave\nSuite 90001\nVancouver\nBC\n1239\n"
          },
          "text",
          [
            "", "", "", "", "", "", ""
          ]
        ],
        ["tel",
          { "type":["work", "voice"], "pref":"1" },
          "uri", "tel:+1-555-555-1234;ext=102"
        ],
        ["tel",
          {
            "type":["work", "cell", "voice", "video", "text"]
          },
          "uri",
          "tel:+1-555-555-1234"
        ],
        ["email",
          { "type":"work" },
          "text", "[email protected]"
        ],
        ["geo", {
          "type":"work"
        }, "uri", "geo:46.772673,-71.282945"],
        ["key",
          { "type":"work" },
          "uri", "https://www.example.com/joe.user/joe.asc"
        ],
        ["tz", {},
          "utc-offset", "-05:00"],
        ["url", { "type":"home" },
          "uri", "https://example.org"]
      ]
    ]
  }

                                Figure 40

  The arrays in Figure 40 with the first member of "adr" represent
  postal addresses.  In the first example, the postal address is given
  as an array of strings and constitutes a structured address.  For
  components of the structured address that are not applicable, an
  empty string is given.  Each member of that array aligns with the
  positions of a vCard as given in [RFC6350].  In this example, the
  following data corresponds to the following positional meanings:

  1.  post office box -- not applicable; empty string

  2.  extended address (e.g., apartment or suite number) -- Suite 1234

  3.  street address -- 4321 Rue Somewhere

  4.  locality (e.g., city) -- Quebec

  5.  region (e.g., state or province) -- QC

  6.  postal code -- G1V 2M2

  7.  country name (full name) -- Canada

  The second example is an unstructured address.  It uses the "label"
  attribute, which is a string containing a newline (\n) character to
  separate address components in an unordered, unspecified manner.
  Note that in this example, the structured address array is still
  given but that each string is an empty string.

Appendix D.  Secure DNS

  Section 5.3 defines the "secureDNS" member to represent secure DNS
  information about domain names.

  DNSSEC provides data integrity for DNS through the digital signing of
  resource records.  To enable DNSSEC, the zone is signed by one or
  more private keys and the signatures are stored as RRSIG records.  To
  complete the chain of trust in the DNS zone hierarchy, a digest of
  each DNSKEY record (which contains the public key) must be loaded
  into the parent zone, stored as DS records, and signed by the
  parent's private key (RRSIG DS record), as indicated in "Resource
  Records for the DNS Security Extensions" [RFC4034].  Creating the DS
  records in the parent zone can be done by the registration authority
  "Domain Name System (DNS) Security Extensions Mapping for the
  Extensible Provisioning Protocol (EPP)" [RFC5910].

  Only DS-related information is provided by RDAP, since other
  information is not generally stored in the registration database.
  Other DNSSEC-related information can be retrieved with other DNS
  tools such as dig.

  The domain object class (Section 5.3) can represent this information
  using either the "dsData" or "keyData" object arrays.  Client
  implementers should be aware that some registries do not collect or
  do not publish all of the secure DNS meta-information.

Appendix E.  Motivations for Using JSON

  This section addresses a common question regarding the use of JSON
  over other data formats, most notably XML.

  It is often pointed out that many DNRs and one RIR support the EPP
  [RFC5730] standard, which is an XML serialized protocol.  The logic
  is that since EPP is a common protocol in the industry, it follows
  that XML would be a more natural choice.  While EPP does influence
  this specification quite a bit, EPP serves a different purpose, which
  is the provisioning of Internet resources between registries and
  accredited registrars and serving a much narrower audience than that
  envisioned for RDAP.

  By contrast, RDAP has a broader audience and is designed for public
  consumption of data.  Experience from RIRs with first generation
  RESTful web services for WHOIS indicate that a large percentage of
  clients operate within browsers and other platforms where full-blown
  XML stacks are not readily available and where JSON is a better fit.

  Additionally, while EPP is used in much of the DNR community it is
  not a universal constant in that industry.  And finally, EPP's use of
  XML predates the specification of JSON.  If EPP had been defined
  today, it may very well have used JSON instead of XML.

  Beyond the specific DNR and RIR communities, the trend in the broader
  Internet industry is also switching to JSON over XML, especially in
  the area of RESTful web services (see [JSON_ascendancy]).  Studies
  have also found that JSON is generally less bulky and consequently
  faster to parse (see [JSON_performance_study]).

Appendix F.  Changes from RFC 7483

  *  Addressed known errata.

  *  Updated references to 7482 to RFC 9082.  Adjusted case of "xxxx"
     used in examples where "XXXX" was previously used, and removed an
     "X" from "XXXXX".  Changed IPv6 address example using "C00" to
     "c00".  Added "a string representing" to the definitions of
     startAddress and endAddress.  Removed "entity" from "Autonomous
     System Number Entity Object Class".  Added "an unsigned 32-bit
     integer" to the definition of startAutnum and endAutnum.  Added "a
     string representing" to the definition of name in the IP network
     and ASN object classes.  Clarified rdapConformance identifier
     registration expectations in Section 4.1.  Changed
     "lunarNic_level_0" to "lunarNIC_level_0".

  *  Clarified that the "value", "rel" and "href" JSON values MUST be
     specified in the "links" array.

  *  Clarified that the "description" array is required in the Notices
     and Remarks data structures and other values are OPTIONAL.

  *  Noted that all members of the "events" and "Public IDs" arrays are
     REQUIRED.

  *  Fix "self" link values in examples.  Changed "http" to "https"
     link values in examples.  Noted that Figure 18 is an example of a
     nameserver object with all "appropriate" values given.  In
     Appendix C, quoted the word "label" in "label attribute".  Added
     reference to "status" definition in the descriptions for IP
     networks and autnums.  Fixed a 404 for the informative reference
     to "The Stealthy Ascendancy of JSON".  Added "boolean" to the
     definition of zoneSigned.

  *  Clarified REQUIRED and OPTIONAL members of the "events" array.

  *  Changed "SHOULD not" to "SHOULD NOT" in Section 5.

  *  Updated normative references (RFC 5226 to RFC 8126, RFC 5988 to
     RFC 8288, RFC 7159 to RFC 8259).  Changed examples using "ns1.xn--
     fo-5ja.example" to split URLs to avoid long lines.

  *  Added acknowledgments.

  *  Changed "The "lang" attribute may appear anywhere in an object
     class or data structure except for in jCard objects" to "The
     "lang" attribute as defined in this section MAY appear anywhere in
     an object class or data structure, except for in jCard objects.
     jCard supports similar functionality by way of the LANGUAGE
     property parameter (see Section 5.1 of RFC 6350 [RFC6350]".

  *  Changed "simple data types conveyed in JSON strings" to "simple
     data types conveyed in JSON primitive types (strings, numbers,
     booleans, and null)".  Changed "In other words, servers are free
     to not include JSON members containing registration data based on
     their own policies" to "In other words, servers are free to omit
     unrequired/optional JSON members containing registration data
     based on their own policies".

  *  Changed "This data structure appears only in the topmost JSON
     object of a response" to "This data structure MUST appear in the
     topmost JSON object of a response".

  *  Changed "Some non-answer responses may return entity bodies with
     information that could be more descriptive" to "Some non-answer
     responses MAY return entity bodies with information that could be
     more descriptive".

  *  Changed "The basic structure of that response is an object class
     containing an error code number (corresponding to the HTTP
     response code) followed by a string named "title" and an array of
     strings named "description"" to "The basic structure of that
     response is an object class containing a REQUIRED error code
     number (corresponding to the HTTP response code) followed by an
     OPTIONAL string named "title" and an OPTIONAL array of strings
     named "description"".

  *  Changed the "Autonomous System Number Object Class" section title
     to "The Autonomous System Number Object Class" for consistency
     with other section titles.  Removed trailing periods in the
     "Terminology and Definitions" section for consistency.  Changed
     instances of "lunarNic" to "lunarNIC" for consistency.  Removed an
     extraneous trailing period after the eventDate description.
     Changed a "." to ";" in the description of the "network" member of
     the domain object class.  Changed "The high-level structure of the
     autnum object class consists of information about the network
     registration" to "The high-level structure of the autnum object
     class consists of information about the Autonomous System number
     registration".  Changed "registry unique" to "registry-unique".

  *  Changed "registrant" to "registrar" in the description of the
     "transfer" event action to address erratum 6158.  Added IANA
     instructions to correct the description of the value in the
     registry.

  *  Added text to Section 4.2 to note that "self" and "related" "href"
     URIs MUST NOT be the same.

  *  Added text to Section 4.2 to describe return of IDNs in LDH name
     format.

  *  Added text to note that the "fn" member of a contact object MAY be
     empty in Section 3.

  *  Added text to clarify rdapConformance requirements in Section 4.1.

  *  Added "obsoletes 7483" to the headers, Abstract, and Introduction.
     Updated BCP 14 boilerplate.  Updated IANA Considerations to note
     that this RFC (a product of the REGEXT Working Group) replaces RFC
     7483.  Changed "simple string" to "simple character string" in
     Sections 3 and 4.7.  Clarified requirement for the "fn" member in
     Section 3.  Modified the requirement for rdapConformance placement
     in Section 4.1.  Changed "jCard" to "vCard" LANGUAGE property
     reference in Section 4.4.  Changed "no use" to "little or no use"
     in Section 5.1.  Added example line wrap note in Section 5.2.
     Modified the definition of "idnTable" in Section 5.3.  Modified
     the dsData and keyData examples in Section 5.3.  Changed
     "2001:c00::/23" to "2001:db8::/32" in Section 5.4.  Expanded the
     definition of "type" in Sections 5.4 and 5.5.  Modified example
     autnums in Section 5.5.  Added text to the Security Considerations
     section to note that DNSSEC information returned in a response
     cannot be trusted directly.

Acknowledgments

  This document is derived from original work on RIR responses in JSON
  by Byron J. Ellacott, Arturo L. Servin, Kaveh Ranjbar, and Andrew L.
  Newton.  Additionally, this document incorporates work on DNR
  responses in JSON by Ning Kong, Linlin Zhou, Jiagui Xie, and Sean
  Shen.

  The components of the DNR object classes are derived from a
  categorization of WHOIS response formats created by Ning Kong, Linlin
  Zhou, Guangqing Deng, Steve Sheng, Francisco Arias, Ray Bellis, and
  Frederico Neves.

  Tom Harrison, Murray Kucherawy, Ed Lewis, Audric Schiltknecht, Naoki
  Kambe, Maarten Bosteels, Mario Loffredo, and Jasdip Singh contributed
  significant review comments and provided clarifying text.  James
  Mitchell provided text regarding the processing of unknown JSON
  attributes and identified issues leading to the remodeling of events.
  Ernie Dainow and Francisco Obispo provided concrete suggestions that
  led to a better variant model for domain names.

  Ernie Dainow provided the background information on the secure DNS
  attributes and objects for domains, informative text on DNSSEC, and
  many other attributes that appear throughout the object classes of
  this document.

  The switch to and incorporation of jCard was performed by Simon
  Perreault.

  Olaf Kolkman and Murray Kucherawy chaired the IETF's WEIRDS Working
  Group from which this document was originally created.  James Galvin
  and Antoin Verschuren chaired the REGEXT Working Group that worked on
  this document.

Authors' Addresses

  Scott Hollenbeck
  Verisign Labs
  12061 Bluemont Way
  Reston, VA 20190
  United States of America

  Email: [email protected]
  URI:   https://www.verisignlabs.com/


  Andy Newton
  Amazon Web Services, Inc.
  13200 Woodland Park Road
  Herndon, VA 20171
  United States of America

  Email: [email protected]

=========================================================================



Internet Engineering Task Force (IETF)                       M. Blanchet
Request for Comments: 9224                                      Viagenie
STD: 95                                                       March 2022
Obsoletes: 7484
Category: Standards Track
ISSN: 2070-1721


  Finding the Authoritative Registration Data Access Protocol (RDAP)
                               Service

Abstract

  This document specifies a method to find which Registration Data
  Access Protocol (RDAP) server is authoritative to answer queries for
  a requested scope, such as domain names, IP addresses, or Autonomous
  System numbers.  This document obsoletes RFC 7484.

Status of This Memo

  This is an Internet Standards Track document.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Further information on
  Internet Standards is available in Section 2 of RFC 7841.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  https://www.rfc-editor.org/info/rfc9224.

Copyright Notice

  Copyright (c) 2022 IETF Trust and the persons identified as the
  document authors.  All rights reserved.

  This document is subject to BCP 78 and the IETF Trust's Legal
  Provisions Relating to IETF Documents
  (https://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Revised BSD License text as described in Section 4.e of the
  Trust Legal Provisions and are provided without warranty as described
  in the Revised BSD License.

Table of Contents

  1.  Introduction
  2.  Conventions Used in This Document
  3.  Structure of the RDAP Bootstrap Service Registries
  4.  Bootstrap Service Registry for Domain Name Space
  5.  Bootstrap Service Registries for Internet Numbers
    5.1.  Bootstrap Service Registry for IPv4 Address Space
    5.2.  Bootstrap Service Registry for IPv6 Address Space
    5.3.  Bootstrap Service Registry for AS Number Space
  6.  Entity
  7.  Non-existent Entries or RDAP URL Values
  8.  Deployment and Implementation Considerations
  9.  Limitations
  10. Formal Definition
    10.1.  Imported JSON Terms
    10.2.  Registry Syntax
  11. Security Considerations
  12. IANA Considerations
    12.1.  Bootstrap Service Registry for IPv4 Address Space
    12.2.  Bootstrap Service Registry for IPv6 Address Space
    12.3.  Bootstrap Service Registry for AS Number Space
    12.4.  Bootstrap Service Registry for Domain Name Space
  13. References
    13.1.  Normative References
    13.2.  Informative References
  Appendix A.  Changes since RFC 7484
  Acknowledgements
  Author's Address

1.  Introduction

  Querying and retrieving registration data from registries are defined
  in the Registration Data Access Protocol (RDAP) [RFC7480] [RFC7481]
  [RFC9082] [RFC9083].  These documents do not specify where to send
  the queries.  This document specifies a method to find which server
  is authoritative to answer queries for the requested scope.

  Top-Level Domains (TLDs), Autonomous System (AS) numbers, and network
  blocks are delegated by IANA to Internet registries such as TLD
  registries and Regional Internet Registries (RIRs) that then issue
  further delegations and maintain information about them.  Thus, the
  bootstrap information needed by RDAP clients is best generated from
  data and processes already maintained by IANA; the relevant
  registries already exist at [ipv4reg], [ipv6reg], [asreg], and
  [domainreg].  This document obsoletes [RFC7484].

  Per this document, IANA has created new registries based on a JSON
  format specified in this document, herein named RDAP Bootstrap
  Service Registries.  These new registries are based on the existing
  entries of the above-mentioned registries.  An RDAP client fetches
  the RDAP Bootstrap Service Registries, extracts the data, and then
  performs a match with the query data to find the authoritative
  registration data server and appropriate query base URL.

2.  Conventions Used in This Document

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
  "OPTIONAL" in this document are to be interpreted as described in
  BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
  capitals, as shown here.

3.  Structure of the RDAP Bootstrap Service Registries

  The RDAP Bootstrap Service Registries, as specified in Section 12
  below, have been made available as JSON [RFC8259] objects, which can
  be retrieved via HTTP from locations specified by IANA.  The JSON
  object for each registry contains a series of members containing
  metadata about the registry such as a version identifier, a timestamp
  of the publication date of the registry, and a description.
  Additionally, a "services" member contains the registry items
  themselves, as an array.  Each item of the array contains a second-
  level array, with two elements, each of them being a third-level
  array.

  Each element of the Services Array is a second-level array with two
  elements: in order, an Entry Array and a Service URL Array.

  The Entry Array contains all entries that have the same set of base
  RDAP URLs.  The Service URL Array contains the list of base RDAP URLs
  usable for the entries found in the Entry Array.  Elements within
  these two arrays are not ordered in any way.

  An example structure of the JSON output of an RDAP Bootstrap Service
  Registry is illustrated:

  {
      "version": "1.0",
      "publication": "YYYY-MM-DDTHH:MM:SSZ",
      "description": "Some text",
      "services": [
        [
          ["entry1", "entry2", "entry3"],
          [
            "https://registry.example.com/myrdap/",
            "http://registry.example.com/myrdap/"
          ]
        ],
        [
          ["entry4"],
          [
            "https://example.org/"
          ]
        ]
      ]
  }

  The formal syntax is described in Section 10.

  The "version" corresponds to the format version of the registry.
  This specification defines version "1.0".

  The syntax of the "publication" value conforms to the Internet date/
  time format [RFC3339].  The value is the latest update date of the
  registry by IANA.

  The optional "description" string can contain a comment regarding the
  content of the bootstrap object.

  Per [RFC7258], in each array of base RDAP URLs, the secure versions
  of the transport protocol SHOULD be preferred and tried first.  For
  example, if the base RDAP URLs array contains both HTTPS and HTTP
  URLs, the bootstrap client SHOULD try the HTTPS version first.

  Base RDAP URLs MUST have a trailing "/" character because they are
  concatenated to the various segments defined in [RFC9082].

  JSON names MUST follow the format recommendations of Section 6 of
  [RFC7480].  Any unrecognized JSON object properties or values MUST be
  ignored by implementations.

  Internationalized Domain Name labels used as entries or base RDAP
  URLs in the registries defined in this document MUST be only
  represented using their A-label form as defined in [RFC5890].

  All Domain Name labels used as entries or base RDAP URLs in the
  registries defined in this document MUST be only represented in
  lowercase.

4.  Bootstrap Service Registry for Domain Name Space

  The JSON output of this registry contains domain label entries
  attached to the root, grouped by base RDAP URLs, as shown in this
  example.

  {
      "version": "1.0",
      "publication": "2024-01-07T10:11:12Z",
      "description": "Some text",
      "services": [
        [
          ["net", "com"],
          [
            "https://registry.example.com/myrdap/"
          ]
        ],
        [
          ["org", "mytld"],
          [
            "https://example.org/"
          ]
        ],
        [
          ["xn--zckzah"],
          [
            "https://example.net/rdap/xn--zckzah/",
            "http://example.net/rdap/xn--zckzah/"
          ]
        ]
      ]
  }

  The domain name's authoritative registration data service is found by
  doing the label-wise longest match of the target domain name with the
  domain values in the Entry Arrays in the IANA "Bootstrap Service
  Registry for Domain Name Space".  The match is done per label, from
  right to left.  If the longest match results in multiple entries,
  then those entries are considered equivalent.  The values contained
  in the Service URL Array of the matching second-level array are the
  valid base RDAP URLs as described in [RFC9082].

  For example, a domain RDAP query for a.b.example.com matches the com
  entry in one of the arrays of the registry.  The base RDAP URL for
  this query is then taken from the second element of the array, which
  is an array of base RDAP URLs valid for this entry.  The client
  chooses one of the base URLs from this array; in this example, it
  chooses the only one available, "https://registry.example.com/
  myrdap/".  The segment specified in [RFC9082] is then appended to the
  base URL to complete the query.  The complete query is then
  "https://registry.example.com/myrdap/domain/a.b.example.com".

  If a domain RDAP query for a.b.example.com matches both com and
  example.com entries in the registry, then the longest match applies
  and the example.com entry is used by the client.

  If the registry contains entries such as com and goodexample.com,
  then a domain RDAP query for example.com only matches the com entry
  because matching is done on a per-label basis.

  The entry for the root of the domain name space is specified as "".

5.  Bootstrap Service Registries for Internet Numbers

  This section discusses IPv4 and IPv6 address space and Autonomous
  System numbers.

  For IP address space, the authoritative registration data service is
  found by doing a longest match of the target address with the values
  of the arrays in the corresponding RDAP Bootstrap Service Registry
  for Address Space.  The longest match is done the same way as in
  packet forwarding: the addresses are converted in binary form and
  then the binary strings are compared to find the longest match up to
  the specified prefix length.  The values contained in the second
  element of the array are the base RDAP URLs as described in
  [RFC9082].  The longest match method enables covering prefixes of a
  larger address space pointing to one base RDAP URL while more
  specific prefixes within the covering prefix are being served by
  another base RDAP URL.

5.1.  Bootstrap Service Registry for IPv4 Address Space

  The JSON output of this registry contains IPv4 prefix entries,
  specified in Classless Inter-domain Routing (CIDR) format [RFC4632]
  and grouped by RDAP URLs, as shown in this example.

  {
      "version": "1.0",
      "publication": "2024-01-07T10:11:12Z",
      "description": "RDAP Bootstrap file for example registries.",
      "services": [
        [
          ["198.51.100.0/24", "192.0.0.0/8"],
          [
            "https://rir1.example.com/myrdap/"
          ]
        ],
        [
          ["203.0.113.0/24", "192.0.2.0/24"],
          [
            "https://example.org/"
          ]
        ],
        [
          ["203.0.113.0/28"],
          [
            "https://example.net/rdaprir2/",
            "http://example.net/rdaprir2/"
          ]
        ]
      ]
  }

  For example, a query for "192.0.2.1/25" matches the "192.0.0.0/8"
  entry and the "192.0.2.0/24" entry in the example registry above.
  The latter is chosen by the client because it is the longest match.
  The base RDAP URL for this query is then taken from the second
  element of the array, which is an array of base RDAP URLs valid for
  this entry.  The client chooses one of the base URLs from this array;
  in this example, it chooses the only one available,
  "https://example.org/".  The {resource} specified in [RFC9082] is
  then appended to the base URL to complete the query.  The complete
  query is then "https://example.org/ip/192.0.2.1/25".

5.2.  Bootstrap Service Registry for IPv6 Address Space

  The JSON output of this registry contains IPv6 prefix entries, using
  [RFC5952] text representation of the address prefixes format, grouped
  by base RDAP URLs, as shown in this example.

  {
      "version": "1.0",
      "publication": "2024-01-07T10:11:12Z",
      "description": "RDAP Bootstrap file for example registries.",
      "services": [
        [
          ["2001:db8::/34"],
          [
            "https://rir2.example.com/myrdap/"
          ]
        ],
        [
          ["2001:db8:4000::/36", "2001:db8:ffff::/48"],
          [
            "https://example.org/"
          ]
        ],
        [
          ["2001:db8:1000::/36"],
          [
            "https://example.net/rdaprir2/",
            "http://example.net/rdaprir2/"
          ]
        ]
      ]
  }

  For example, a query for "2001:db8:1000::/48" matches the
  "2001:db8::/34" entry and the "2001:db8:1000::/36" entry in the
  example registry above.  The latter is chosen by the client because
  it is the longest match.  The base RDAP URL for this query is then
  taken from the second element of the array, which is an array of base
  RDAP URLs valid for this entry.  The client chooses one of the base
  URLs from this array; in this example, it chooses
  "https://example.net/rdaprir2/" because it's the secure version of
  the protocol.  The segment specified in [RFC9082] is then appended to
  the base URL to complete the query.  The complete query is therefore
  "https://example.net/rdaprir2/ip/2001:db8:1000::/48".  If the target
  RDAP server does not answer, the client can then use another URL
  prefix from the array.

5.3.  Bootstrap Service Registry for AS Number Space

  The JSON output of this registry contains entries for AS number
  ranges, grouped by base RDAP URLs, as shown in this example.  The
  Entry Array is an array containing the list of AS number ranges
  served by the base RDAP URLs found in the second element.  Each
  element of the array contains two AS numbers represented in decimal
  format, separated by a hyphen, that represents the range of AS
  numbers between the two AS numbers (inclusive), where values are in
  increasing order (e.g., 100-200, not 200-100).  A single AS number is
  represented as a range of two identical AS numbers.  AS numbers are
  represented as 'asplain' as defined in [RFC5396].  Ranges MUST NOT
  overlap.

  {
      "version": "1.0",
      "publication": "2024-01-07T10:11:12Z",
      "description": "RDAP Bootstrap file for example registries.",
      "services": [
        [
          ["64496-64496"],
          [
            "https://rir3.example.com/myrdap/"
          ]
        ],
        [
          ["64497-64510", "65536-65551"],
          [
            "https://example.org/"
          ]
        ],
        [
          ["64512-65534"],
          [
            "http://example.net/rdaprir2/",
            "https://example.net/rdaprir2/"
          ]
        ]
      ]
  }

  For example, a query for AS 65411 matches the 64512-65534 entry in
  the example registry above.  The base RDAP URL for this query is then
  taken from the second element of the array, which is an array of base
  RDAP URLs valid for this entry.  The client chooses one of the base
  URLs from this array; in this example, it chooses
  "https://example.net/rdaprir2/".  The segment specified in [RFC9082]
  is then appended to the base URL to complete the query.  The complete
  query is, therefore, "https://example.net/rdaprir2/autnum/65411".  If
  the server does not answer, the client can then use another URL
  prefix from the array.

6.  Entity

  Entities (such as contacts, registrants, or registrars) can be
  queried by handle as described in [RFC9082].  Since there is no
  global name space for entities, this document does not describe how
  to find the authoritative RDAP server for entities.  However, it is
  possible that, if the entity identifier was received from a previous
  query, the same RDAP server could be queried for that entity, or the
  entity identifier itself is a fully qualified URL that can be
  queried.  The mechanism described in [RFC8521] MAY also be used.

7.  Non-existent Entries or RDAP URL Values

  The registries may not contain the requested value.  In these cases,
  there is no known RDAP server for that requested value, and the
  client SHOULD provide an appropriate error message to the user.

8.  Deployment and Implementation Considerations

  This method relies on the fact that RDAP clients are fetching the
  IANA registries to then find the servers locally.  Clients SHOULD NOT
  fetch the registry on every RDAP request.  Clients SHOULD cache the
  registry, but use underlying protocol signaling, such as the HTTP
  Expires header field [RFC7234], to identify when it is time to
  refresh the cached registry.

  Some authorities of registration data may work together on sharing
  their information for a common service, including mutual redirection
  [REDIRECT-RDAP].

  When a new object is allocated, such as a new AS range, a new TLD, or
  a new IP address range, there is no guarantee that this new object
  will have an entry in the corresponding bootstrap RDAP registry,
  since the setup of the RDAP server for this new entry may become live
  and registered later.  Therefore, the clients should expect that even
  if an object, such as TLD, IP address range, or AS range is
  allocated, the existence of the entry in the corresponding bootstrap
  registry is not guaranteed.

9.  Limitations

  This method does not provide a direct way to find authoritative RDAP
  servers for any other objects than the ones described in this
  document.  In particular, the following objects are not bootstrapped
  with the method described in this document:

  *  entities

  *  queries using search patterns that do not contain a terminating
     string that matches some entries in the registries

  *  nameservers

  *  help

10.  Formal Definition

  This section is the formal definition of the registries.  The
  structure of JSON objects and arrays using a set of primitive
  elements is defined in [RFC8259].  Those elements are used to
  describe the JSON structure of the registries.

10.1.  Imported JSON Terms

  OBJECT:  a JSON object, defined in Section 4 of [RFC8259]

  MEMBER:  a member of a JSON object, defined in Section 4 of [RFC8259]

  MEMBER-NAME:  the name of a MEMBER, defined as a "string" in
     Section 4 of [RFC8259]

  MEMBER-VALUE:  the value of a MEMBER, defined as a "value" in
     Section 4 of [RFC8259]

  ARRAY:  an array, defined in Section 5 of [RFC8259]

  ARRAY-VALUE:  an element of an ARRAY, defined in Section 5 of
     [RFC8259]

  STRING:  a "string", as defined in Section 7 of [RFC8259]

10.2.  Registry Syntax

  Using the above terms for the JSON structures, the syntax of a
  registry is defined as follows:

  rdap-bootstrap-registry:  an OBJECT containing a MEMBER version and a
     MEMBER publication, an optional MEMBER description, and a MEMBER
     services-list

  version:  a MEMBER with MEMBER-NAME "version" and MEMBER-VALUE a
     STRING

  publication:  a MEMBER with MEMBER-NAME "publication" and MEMBER-
     VALUE a STRING

  description:  a MEMBER with MEMBER-NAME "description" and MEMBER-
     VALUE a STRING

  services-list:  a MEMBER with MEMBER-NAME "services" and MEMBER-VALUE
     a services-array

  services-array:  an ARRAY, where each ARRAY-VALUE is a service

  service:  an ARRAY of 2 elements, where the first ARRAY-VALUE is an
     entry-list and the second ARRAY-VALUE is a service-uri-list

  entry-list:  an ARRAY, where each ARRAY-VALUE is an entry

  entry:  a STRING

  service-uri-list:  an ARRAY, where each ARRAY-VALUE is a service-uri

  service-uri:  a STRING

11.  Security Considerations

  By providing a bootstrap method to find RDAP servers, this document
  helps to ensure that the end users will get the RDAP data from an
  authoritative source instead of from rogue sources.  The method has
  the same security properties as the RDAP protocols themselves.  The
  transport used to access the registries uses TLS [RFC8446].

  Additional considerations on using RDAP are described in [RFC7481].

12.  IANA Considerations

  IANA has created the RDAP Bootstrap Services Registries listed below
  and made them available as JSON objects.  The contents of these
  registries are described in Sections 3, 4, and 5, with the formal
  syntax specified in Section 10.  The registries MUST be accessible
  only through HTTPS (TLS [RFC8446]) transport.

  The process for adding or updating entries in these registries
  differs from the normal IANA registry processes: these registries are
  generated from the data, processes, and policies maintained by IANA
  in their allocation registries ([ipv4reg], [ipv6reg], [asreg], and
  [domainreg]), with the addition of new RDAP server information.

  IANA updates RDAP Bootstrap Services Registries entries from the
  allocation registries as those registries are updated.

  This document does not change any policies related to the allocation
  registries; IANA has provided a mechanism for collecting the RDAP
  server information.

  IANA has created a new top-level category on the Protocol Registries
  page: <https://www.iana.org/protocols>.  The group is called
  "Registration Data Access Protocol (RDAP)".  Each of the RDAP
  Bootstrap Services Registries has been made available for on-demand
  download in the JSON format by the general public, and that
  registry's URI is listed directly on the Protocol Registries page.

  Other normal registries will be added to this group by other
  documents, but the reason the URIs for these registries are clearly
  listed on the main page is to make those URIs obvious to implementers
  -- these are registries that will be accessed by software, as well as
  by humans using them for reference information.

  Because these registries will be accessed by software, the download
  demand for the RDAP Bootstrap Services Registries may be unusually
  high compared to normal IANA registries.  The technical
  infrastructure by which registries are published has been put in
  place by IANA to support the load.  Since the publication of
  [RFC7484], no issues have been reported regarding the load or the
  service.

  As discussed in Section 8, software that accesses these registries
  will depend on the HTTP Expires header field to limit their query
  rate.  It is, therefore, important for that header field to be
  properly set to provide timely information as the registries change,
  while maintaining a reasonable load on the IANA servers.

  The HTTP Content-Type returned to clients accessing these JSON-
  formatted registries MUST be "application/json", as defined in
  [RFC8259].

  Because of how information in the RDAP Bootstrap Services Registries
  is grouped and formatted, the registry entries may not be sortable.
  It is, therefore, not required or expected that the entries be
  ordered in any way.

12.1.  Bootstrap Service Registry for IPv4 Address Space

  Entries in this registry contain at least the following:

  *  a CIDR [RFC4632] specification of the network block being
     registered

  *  one or more URLs that provide the RDAP service regarding this
     registration

12.2.  Bootstrap Service Registry for IPv6 Address Space

  Entries in this registry contain at least the following:

  *  an IPv6 prefix [RFC5952] specification of the network block being
     registered

  *  one or more URLs that provide the RDAP service regarding this
     registration

12.3.  Bootstrap Service Registry for AS Number Space

  Entries in this registry contain at least the following:

  *  a range of Autonomous System numbers being registered

  *  one or more URLs that provide the RDAP service regarding this
     registration

12.4.  Bootstrap Service Registry for Domain Name Space

  Entries in this registry contain at least the following:

  *  a domain name attached to the root being registered

  *  one or more URLs that provide the RDAP service regarding this
     registration

13.  References

13.1.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119,
             DOI 10.17487/RFC2119, March 1997,
             <https://www.rfc-editor.org/info/rfc2119>.

  [RFC3339]  Klyne, G. and C. Newman, "Date and Time on the Internet:
             Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
             <https://www.rfc-editor.org/info/rfc3339>.

  [RFC4632]  Fuller, V. and T. Li, "Classless Inter-domain Routing
             (CIDR): The Internet Address Assignment and Aggregation
             Plan", BCP 122, RFC 4632, DOI 10.17487/RFC4632, August
             2006, <https://www.rfc-editor.org/info/rfc4632>.

  [RFC5396]  Huston, G. and G. Michaelson, "Textual Representation of
             Autonomous System (AS) Numbers", RFC 5396,
             DOI 10.17487/RFC5396, December 2008,
             <https://www.rfc-editor.org/info/rfc5396>.

  [RFC5890]  Klensin, J., "Internationalized Domain Names for
             Applications (IDNA): Definitions and Document Framework",
             RFC 5890, DOI 10.17487/RFC5890, August 2010,
             <https://www.rfc-editor.org/info/rfc5890>.

  [RFC5952]  Kawamura, S. and M. Kawashima, "A Recommendation for IPv6
             Address Text Representation", RFC 5952,
             DOI 10.17487/RFC5952, August 2010,
             <https://www.rfc-editor.org/info/rfc5952>.

  [RFC7258]  Farrell, S. and H. Tschofenig, "Pervasive Monitoring Is an
             Attack", BCP 188, RFC 7258, DOI 10.17487/RFC7258, May
             2014, <https://www.rfc-editor.org/info/rfc7258>.

  [RFC7480]  Newton, A., Ellacott, B., and N. Kong, "HTTP Usage in the
             Registration Data Access Protocol (RDAP)", STD 95,
             RFC 7480, DOI 10.17487/RFC7480, March 2015,
             <https://www.rfc-editor.org/info/rfc7480>.

  [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
             2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
             May 2017, <https://www.rfc-editor.org/info/rfc8174>.

  [RFC8259]  Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
             Interchange Format", STD 90, RFC 8259,
             DOI 10.17487/RFC8259, December 2017,
             <https://www.rfc-editor.org/info/rfc8259>.

13.2.  Informative References

  [asreg]    IANA, "Autonomous System (AS) Numbers",
             <https://www.iana.org/assignments/as-numbers>.

  [domainreg]
             IANA, "Root Zone Database",
             <https://www.iana.org/domains/root/db>.

  [ipv4reg]  IANA, "IANA IPv4 Address Space Registry",
             <https://www.iana.org/assignments/ipv4-address-space>.

  [ipv6reg]  IANA, "IPv6 Global Unicast Address Assignments",
             <https://www.iana.org/assignments/ipv6-unicast-address-
             assignments>.

  [REDIRECT-RDAP]
             Martinez, C.M., Ed., Zhou, L., Ed., and G. Rada,
             "Redirection Service for Registration Data Access
             Protocol", Work in Progress, Internet-Draft, draft-ietf-
             weirds-redirects-04, July 2014,
             <https://datatracker.ietf.org/doc/html/draft-ietf-weirds-
             redirects-04>.

  [RFC7071]  Borenstein, N. and M. Kucherawy, "A Media Type for
             Reputation Interchange", RFC 7071, DOI 10.17487/RFC7071,
             November 2013, <https://www.rfc-editor.org/info/rfc7071>.

  [RFC7234]  Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke,
             Ed., "Hypertext Transfer Protocol (HTTP/1.1): Caching",
             RFC 7234, DOI 10.17487/RFC7234, June 2014,
             <https://www.rfc-editor.org/info/rfc7234>.

  [RFC7481]  Hollenbeck, S. and N. Kong, "Security Services for the
             Registration Data Access Protocol (RDAP)", STD 95,
             RFC 7481, DOI 10.17487/RFC7481, March 2015,
             <https://www.rfc-editor.org/info/rfc7481>.

  [RFC7484]  Blanchet, M., "Finding the Authoritative Registration Data
             (RDAP) Service", RFC 7484, DOI 10.17487/RFC7484, March
             2015, <https://www.rfc-editor.org/info/rfc7484>.

  [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
             Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
             <https://www.rfc-editor.org/info/rfc8446>.

  [RFC8521]  Hollenbeck, S. and A. Newton, "Registration Data Access
             Protocol (RDAP) Object Tagging", BCP 221, RFC 8521,
             DOI 10.17487/RFC8521, November 2018,
             <https://www.rfc-editor.org/info/rfc8521>.

  [RFC9082]  Hollenbeck, S. and A. Newton, "Registration Data Access
             Protocol (RDAP) Query Format", STD 95, RFC 9082,
             DOI 10.17487/RFC9082, June 2021,
             <https://www.rfc-editor.org/info/rfc9082>.

  [RFC9083]  Hollenbeck, S. and A. Newton, "JSON Responses for the
             Registration Data Access Protocol (RDAP)", STD 95,
             RFC 9083, DOI 10.17487/RFC9083, June 2021,
             <https://www.rfc-editor.org/info/rfc9083>.

Appendix A.  Changes since RFC 7484

  There are no substantive changes except for minor clarifications.
  This update is primarily to meet the requirements for moving to an
  Internet Standard.

Acknowledgements

  The WEIRDS Working Group had multiple discussions on this topic,
  including a session during IETF 84, where various methods such as in-
  DNS and others were debated.  The idea of using IANA registries was
  discovered by the author during discussions with his colleagues as
  well as by a comment from Andy Newton.  All the people involved in
  these discussions are herein acknowledged.  Linlin Zhou, Jean-
  Philippe Dionne, John Levine, Kim Davies, Ernie Dainow, Scott
  Hollenbeck, Arturo Servin, Andy Newton, Murray Kucherawy, Tom
  Harrison, Naoki Kambe, Alexander Mayrhofer, Edward Lewis, Pete
  Resnick, Alessandro Vesely, Bert Greevenbosch, Barry Leiba, Jari
  Arkko, Kathleen Moriaty, Stephen Farrell, Richard Barnes, and Jean-
  Francois Tremblay provided input and suggestions to the first version
  of this document.

  Guillaume Leclanche was a coauthor of this document for some
  revisions; his support is therein acknowledged and greatly
  appreciated.  The section on formal definition was inspired by
  Section 6.2 of [RFC7071].  This new version [This document] received
  comments and suggestions from Gavin Brown, Patrick Mevzek, John
  Levine, Jasdip Singh, George Michaelson, Scott Hollenbeck, Russ
  Housley, Joel Halpern, Lars Eggert, Benjamin Kaduk, Scott Kelly, Éric
  Vyncke, John Scudder, Erik Kline, and Robert Wilton.  Errata for RFC
  7484 were submitted by Pieter Vandepitte and were applied to this
  document.

Author's Address

  Marc Blanchet
  Viagenie
  246 Aberdeen
  Quebec QC G1R 2E1
  Canada
  Email: [email protected]
  URI:   https://viagenie.ca