Network Working Group                                    D. Eastlake 3rd
Request for Comments: 5395                              Stellar Switches
BCP: 42                                                    November 2008
Obsoletes: 2929
Updates: 1183, 3597
Category: Best Current Practice


             Domain Name System (DNS) IANA Considerations

Status of This Memo

  This document specifies an Internet Best Current Practices for the
  Internet Community, and requests discussion and suggestions for
  improvements.  Distribution of this memo is unlimited.

Copyright Notice

  Copyright (c) 2008 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.

Abstract

  Internet Assigned Number Authority (IANA) parameter assignment
  considerations are specified for the allocation of Domain Name System
  (DNS) resource record types, CLASSes, operation codes, error codes,
  DNS protocol message header bits, and AFSDB resource record subtypes.

















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Table of Contents

  1. Introduction ....................................................2
     1.1. Terminology ................................................2
  2. DNS Query/Response Headers ......................................3
     2.1. One Spare Bit? .............................................4
     2.2. OpCode Assignment ..........................................4
     2.3. RCODE Assignment ...........................................4
  3. DNS Resource Records ............................................6
     3.1. RRTYPE IANA Considerations .................................7
          3.1.1. DNS RRTYPE Allocation Policy ........................8
          3.1.2. DNS RRTYPE Expert Guidelines ........................9
          3.1.3. Special Note on the OPT RR ..........................9
          3.1.4. The AFSDB RR Subtype Field .........................10
     3.2. RR CLASS IANA Considerations ..............................10
     3.3. Label Considerations ......................................12
          3.3.1. Label Types ........................................12
          3.3.2. Label Contents and Use .............................12
  4. Security Considerations ........................................13
  5. IANA Considerations ............................................13
  Appendix A. RRTYPE Allocation Template ............................14
  Normative References ..............................................15
  Informative References ............................................16

1.  Introduction

  The Domain Name System (DNS) provides replicated distributed secure
  hierarchical databases that store "resource records" (RRs) under
  domain names.  DNS data is structured into CLASSes and zones that can
  be independently maintained.  See [RFC1034], [RFC1035], [RFC2136],
  [RFC2181], and [RFC4033], familiarity with which is assumed.

  This document provides, either directly or by reference, the general
  IANA parameter assignment considerations that apply across DNS query
  and response headers and all RRs.  There may be additional IANA
  considerations that apply to only a particular RRTYPE or
  query/response OpCode.  See the specific RFC defining that RRTYPE or
  query/response OpCode for such considerations if they have been
  defined, except for AFSDB RR considerations [RFC1183], which are
  included herein.  This RFC obsoletes [RFC2929].

  IANA currently maintains a web page of DNS parameters available from
  http://www.iana.org.

1.1.  Terminology

  "IETF Standards Action", "IETF Review", "Specification Required", and
  "Private Use" are as defined in [RFC5226].



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2.  DNS Query/Response Headers

  The header for DNS queries and responses contains field/bits in the
  following diagram taken from [RFC2136] and [RFC2929]:

                                             1  1  1  1  1  1
               0  1  2  3  4  5  6  7  8  9  0  1  2  3  4  5
              +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
              |                      ID                       |
              +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
              |QR|   OpCode  |AA|TC|RD|RA| Z|AD|CD|   RCODE   |
              +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
              |                QDCOUNT/ZOCOUNT                |
              +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
              |                ANCOUNT/PRCOUNT                |
              +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
              |                NSCOUNT/UPCOUNT                |
              +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
              |                    ARCOUNT                    |
              +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+

  The ID field identifies the query and is echoed in the response so
  they can be matched.

  The QR bit indicates whether the header is for a query or a response.

  The AA, TC, RD, RA, AD, and CD bits are each theoretically meaningful
  only in queries or only in responses, depending on the bit.  However,
  some DNS implementations copy the query header as the initial value
  of the response header without clearing bits.  Thus, any attempt to
  use a "query" bit with a different meaning in a response or to define
  a query meaning for a "response" bit is dangerous, given existing
  implementation.  Such meanings may only be assigned by an IETF
  Standards Action.

  The unsigned integer fields query count (QDCOUNT), answer count
  (ANCOUNT), authority count (NSCOUNT), and additional information
  count (ARCOUNT) express the number of records in each section for all
  OpCodes except Update [RFC2136].  These fields have the same
  structure and data type for Update but are instead the counts for the
  zone (ZOCOUNT), prerequisite (PRCOUNT), update (UPCOUNT), and
  additional information (ARCOUNT) sections.









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2.1.  One Spare Bit?

  There have been ancient DNS implementations for which the Z bit being
  on in a query meant that only a response from the primary server for
  a zone is acceptable.  It is believed that current DNS
  implementations ignore this bit.

  Assigning a meaning to the Z bit requires an IETF Standards Action.

2.2.  OpCode Assignment

  Currently DNS OpCodes are assigned as follows:

        OpCode Name                               Reference

         0     Query                              [RFC1035]
         1     IQuery (Inverse Query, Obsolete)   [RFC3425]
         2     Status                             [RFC1035]
         3     available for assignment
         4     Notify                             [RFC1996]
         5     Update                             [RFC2136]
        6-15   available for assignment

  New OpCode assignments require an IETF Standards Action as modified
  by [RFC4020].

2.3.  RCODE Assignment

  It would appear from the DNS header above that only four bits of
  RCODE, or response/error code, are available.  However, RCODEs can
  appear not only at the top level of a DNS response but also inside
  OPT RRs [RFC2671], TSIG RRs [RFC2845], and TKEY RRs [RFC2930].  The
  OPT RR provides an 8-bit extension resulting in a 12-bit RCODE field,
  and the TSIG and TKEY RRs have a 16-bit RCODE field.

















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  Error codes appearing in the DNS header and in these three RR types
  all refer to the same error code space with the single exception of
  error code 16, which has a different meaning in the OPT RR from its
  meaning in other contexts.  See table below.

       RCODE   Name    Description                        Reference
       Decimal
         Hexadecimal
        0    NoError   No Error                           [RFC1035]
        1    FormErr   Format Error                       [RFC1035]
        2    ServFail  Server Failure                     [RFC1035]
        3    NXDomain  Non-Existent Domain                [RFC1035]
        4    NotImp    Not Implemented                    [RFC1035]
        5    Refused   Query Refused                      [RFC1035]
        6    YXDomain  Name Exists when it should not     [RFC2136]
        7    YXRRSet   RR Set Exists when it should not   [RFC2136]
        8    NXRRSet   RR Set that should exist does not  [RFC2136]
        9    NotAuth   Server Not Authoritative for zone  [RFC2136]
       10    NotZone   Name not contained in zone         [RFC2136]
       11 - 15         Available for assignment
       16    BADVERS   Bad OPT Version                    [RFC2671]
       16    BADSIG    TSIG Signature Failure             [RFC2845]
       17    BADKEY    Key not recognized                 [RFC2845]
       18    BADTIME   Signature out of time window       [RFC2845]
       19    BADMODE   Bad TKEY Mode                      [RFC2930]
       20    BADNAME   Duplicate key name                 [RFC2930]
       21    BADALG    Algorithm not supported            [RFC2930]
       22    BADTRUC   Bad Truncation                     [RFC4635]
       23 - 3,840
   0x0017 - 0x0F00     Available for assignment

    3,841 - 4,095
   0x0F01 - 0x0FFF     Private Use

    4,096 - 65,534
   0x1000 - 0xFFFE     Available for assignment

   65,535
   0xFFFF              Reserved, can only be allocated by an IETF
                       Standards Action.

  Since it is important that RCODEs be understood for interoperability,
  assignment of new RCODE listed above as "available for assignment"
  requires an IETF Review.







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3.  DNS Resource Records

  All RRs have the same top-level format, shown in the figure below
  taken from [RFC1035].

                                      1  1  1  1  1  1
        0  1  2  3  4  5  6  7  8  9  0  1  2  3  4  5
      +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      |                                               |
      /                                               /
      /                      NAME                     /
      /                                               /
      +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      |                      TYPE                     |
      +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      |                     CLASS                     |
      +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      |                      TTL                      |
      |                                               |
      +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
      |                   RDLENGTH                    |
      +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--|
      /                     RDATA                     /
      /                                               /
      +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+

  NAME is an owner name, i.e., the name of the node to which this
  resource record pertains.  NAMEs are specific to a CLASS as described
  in section 3.2.  NAMEs consist of an ordered sequence of one or more
  labels, each of which has a label type [RFC1035] [RFC2671].

  TYPE is a 2-octet unsigned integer containing one of the RRTYPE
  codes.  See section 3.1.

  CLASS is a 2-octet unsigned integer containing one of the RR CLASS
  codes.  See section 3.2.

  TTL is a 4-octet (32-bit) unsigned integer that specifies, for data
  TYPEs, the number of seconds that the resource record may be cached
  before the source of the information should again be consulted.  Zero
  is interpreted to mean that the RR can only be used for the
  transaction in progress.

  RDLENGTH is an unsigned 16-bit integer that specifies the length in
  octets of the RDATA field.






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  RDATA is a variable length string of octets that constitutes the
  resource.  The format of this information varies according to the
  TYPE and, in some cases, the CLASS of the resource record.

3.1.  RRTYPE IANA Considerations

  There are three subcategories of RRTYPE numbers: data TYPEs, QTYPEs,
  and Meta-TYPEs.

  Data TYPEs are the means of storing data.  QTYPES can only be used in
  queries.  Meta-TYPEs designate transient data associated with a
  particular DNS message and, in some cases, can also be used in
  queries.  Thus far, data TYPEs have been assigned from 1 upward plus
  the block from 100 through 103 and from 32,768 upward, while Q and
  Meta-TYPEs have been assigned from 255 downward except for the OPT
  Meta-RR, which is assigned TYPE 41.  There have been DNS
  implementations that made caching decisions based on the top bit of
  the bottom byte of the RRTYPE.

  There are currently three Meta-TYPEs assigned: OPT [RFC2671], TSIG
  [RFC2845], and TKEY [RFC2930].  There are currently five QTYPEs
  assigned: * (ALL), MAILA, MAILB, AXFR, and IXFR.

  RRTYPEs have mnemonics that must be completely disjoint from the
  mnemonics used for CLASSes and that must match the following regular
  expression:

        [A-Z][A-Z0-9-]*

  Considerations for the allocation of new RRTYPEs are as follows:

    Decimal
  Hexadecimal

       0
  0x0000 - RRTYPE zero is used as a special indicator for the SIG (0)
         RR [RFC2931] and in other circumstances, and it must never be
         allocated for ordinary use.

       1 - 127
  0x0001 - 0x007F - Remaining RRTYPEs in this range are assigned for
           data TYPEs by the DNS RRTYPE Allocation Policy as specified
           in Section 3.1.1.

     128 - 255
  0x0080 - 0x00FF - Remaining RRTYPEs in this range are assigned for Q
           and Meta TYPEs by the DNS RRTYPE Allocation Policy as
           specified in Section 3.1.1.



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     256 - 61,439
  0x0100 - 0xEFFF - Remaining RRTYPEs in this range are assigned for
           data RRTYPEs by the DNS RRTYPE Allocation Policy as
           specified in Section 3.1.1.  (32,768 and 32,769 (0x8000 and
           0x8001) have been assigned.)

  61,440 - 65,279
  0xF000 - 0xFEFF - Reserved for future use.  IETF Review required to
           define use.

  65,280 - 65,534
  0xFF00 - 0xFFFE - Private Use.

  65,535
  0xFFFF - Reserved; can only be assigned by an IETF Standards Action.

3.1.1.  DNS RRTYPE Allocation Policy

  Parameter values specified in Section 3.1 above, as assigned based on
  DNS RRTYPE Allocation Policy, are allocated by Expert Review if they
  meet the two requirements listed below.  There will be a pool of a
  small number of Experts appointed by the IESG.  Each application will
  be ruled on by an Expert selected by IANA.  In any case where the
  selected Expert is unavailable or states they have a conflict of
  interest, IANA may select another Expert from the pool.

  Some guidelines for the Experts are given in Section 3.1.2.  RRTYPEs
  that do not meet the requirements below may nonetheless be allocated
  by IETF Standards Action as modified by [RFC4020].

  1. A complete template as specified in Appendix A has been posted for
     three weeks to the [email protected] mailing list before
     the Expert Review decision.

     Note that partially completed or draft templates may be posted
     directly by the applicant for comment and discussion, but the
     formal posting to start the three week period is made by the
     Expert.

  2. The RR for which an RRTYPE code is being requested is either (a) a
     data TYPE that can be handled as an Unknown RR as described in
     [RFC3597] or (b) a Meta-Type whose processing is optional, i.e.,
     it is safe to simply discard RRs with that Meta-Type in queries or
     responses.

     Note that such RRs may include additional section processing,
     provided such processing is optional.




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  No less than three weeks and no more than six weeks after a completed
  template has been formally posted to [email protected], the
  selected Expert shall post a message, explicitly accepting or
  rejecting the application, to IANA, [email protected], and
  the email address provided by the applicant.  If the Expert does not
  post such a message, the application shall be considered rejected but
  may be re-submitted to IANA.

  IANA shall maintain a public archive of approved templates.

3.1.2.  DNS RRTYPE Expert Guidelines

  The selected DNS RRTYPE Expert is required to monitor discussion of
  the proposed RRTYPE, which may occur on the [email protected]
  mailing list, and may consult with other technical experts as
  necessary.  The Expert should normally reject any RRTYPE allocation
  request that meets one or more of the following criterion:

  1. Was documented in a manner that was not sufficiently clear to
     evaluate or implement.

  2. The proposed RRTYPE or RRTYPEs affect DNS processing and do not
     meet the criteria in point 2 of Section 3.1.1 above.

  3. The documentation of the proposed RRTYPE or RRTYPEs is incomplete.
     (Additional documentation can be provided during the public
     comment period or by the Expert.)

  4. Application use as documented makes incorrect assumptions about
     DNS protocol behavior, such as wild cards, CNAME, DNAME, etc.

  5. An excessive number of RRTYPE values is being requested when the
     purpose could be met with a smaller number or with Private Use
     values.

3.1.3.  Special Note on the OPT RR

  The OPT (OPTion) RR (RRTYPE 41) and its IANA Considerations are
  specified in [RFC2671].  Its primary purpose is to extend the
  effective field size of various DNS fields including RCODE, label
  type, OpCode, flag bits, and RDATA size.  In particular, for
  resolvers and servers that recognize it, it extends the RCODE field
  from 4 to 12 bits.








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3.1.4.  The AFSDB RR Subtype Field

  The AFSDB RR [RFC1183] is a CLASS-insensitive RR that has the same
  RDATA field structure as the MX RR, but the 16-bit unsigned integer
  field at the beginning of the RDATA is interpreted as a subtype as
  follows:

    Decimal
  Hexadecimal

       0
  0x0000 - Reserved; allocation requires IETF Standards Action.

       1
  0x0001 - Andrews File Service v3.0 Location Service [RFC1183].

       2
  0x0002 - DCE/NCA root cell directory node [RFC1183].

       3 - 65,279
  0x0003 - 0xFEFF - Allocation by IETF Review.

  65,280 - 65,534
  0xFF00 - 0xFFFE - Private Use.

  65,535
  0xFFFF - Reserved; allocation requires IETF Standards Action.

3.2.  RR CLASS IANA Considerations

  There are currently two subcategories of DNS CLASSes: normal,
  data-containing classes and QCLASSes that are only meaningful in
  queries or updates.

  DNS CLASSes have been little used but constitute another dimension of
  the DNS distributed database.  In particular, there is no necessary
  relationship between the name space or root servers for one data
  CLASS and those for another data CLASS.  The same DNS NAME can have
  completely different meanings in different CLASSes.  The label types
  are the same, and the null label is usable only as root in every
  CLASS.  As global networking and DNS have evolved, the IN, or
  Internet, CLASS has dominated DNS use.

  As yet there has not be a requirement for "meta-CLASSes".  That would
  be a CLASS to designate transient data associated with a particular
  DNS message, which might be usable in queries.  However, it is
  possible that there might be a future requirement for one or more
  "meta-CLASSes".



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  CLASSes have mnemonics that must be completely disjoint from the
  mnemonics used for RRTYPEs and that must match the following regular
  expression:

        [A-Z][A-Z0-9-]*

  The current CLASS assignments and considerations for future
  assignments are as follows:

    Decimal
  Hexadecimal

       0
  0x0000 - Reserved; assignment requires an IETF Standards Action.

       1
  0x0001 - Internet (IN).

       2
  0x0002 - Available for assignment by IETF Review as a data CLASS.

       3
  0x0003 - Chaos (CH) [Moon1981].

       4
  0x0004 - Hesiod (HS) [Dyer1987].

       5 - 127
  0x0005 - 0x007F - Available for assignment by IETF Review for data
                    CLASSes only.

     128 - 253
  0x0080 - 0x00FD - Available for assignment by IETF Review for
                    QCLASSes and meta-CLASSes only.

     254
  0x00FE - QCLASS NONE [RFC2136].

     255
  0x00FF - QCLASS * (ANY) [RFC1035].

     256 - 32,767
  0x0100 - 0x7FFF - Assigned by IETF Review.

  32,768 - 57,343
  0x8000 - 0xDFFF - Assigned for data CLASSes only, based on
                    Specification Required as defined in [RFC5226].




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  57,344 - 65,279
  0xE000 - 0xFEFF - Assigned for QCLASSes and meta-CLASSes only, based
                    on Specification Required as defined in [RFC5226].

  65,280 - 65,534
  0xFF00 - 0xFFFE - Private Use.

  65,535
  0xFFFF - Reserved; can only be assigned by an IETF Standards Action.

3.3.  Label Considerations

  DNS NAMEs are sequences of labels [RFC1035].

3.3.1.  Label Types

  At the present time, there are two categories of label types: data
  labels and compression labels.  Compression labels are pointers to
  data labels elsewhere within an RR or DNS message and are intended to
  shorten the wire encoding of NAMEs.

  The two existing data label types are sometimes referred to as Text
  and Binary.  Text labels can, in fact, include any octet value
  including zero-value octets, but many current uses involve only
  [US-ASCII].  For retrieval, Text labels are defined to treat ASCII
  upper and lower case letter codes as matching [RFC4343].  Binary
  labels are bit sequences [RFC2673].  The Binary label type is
  Experimental [RFC3363].

  IANA considerations for label types are given in [RFC2671].

3.3.2.  Label Contents and Use

  The last label in each NAME is "ROOT", which is the zero-length
  label.  By definition, the null or ROOT label cannot be used for any
  other NAME purpose.

  NAMEs are local to a CLASS.  The Hesiod [Dyer1987] and Chaos
  [Moon1981] CLASSes are for essentially local use.  The IN, or
  Internet, CLASS is thus the only DNS CLASS in global use on the
  Internet at this time.

  A somewhat out-of-date description of name allocation in the IN Class
  is given in [RFC1591].  Some information on reserved top-level domain
  names is in BCP 32 [RFC2606].






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4.  Security Considerations

  This document addresses IANA considerations in the allocation of
  general DNS parameters, not security.  See [RFC4033], [RFC4034], and
  [RFC4035] for secure DNS considerations.

5.  IANA Considerations

  This document consists entirely of DNS IANA Considerations and
  includes the following changes from its predecessor [RFC2929].  It
  affects the DNS Parameters registry and its subregistries, which are
  available from http://www.iana.org.

  1. In the Domain Name System "Resource record (RR) TYPES and QTYPEs"
     registry, it changes most "IETF Consensus" and all "Specification
     Required" allocation policies for RRTYPEs to be "DNS TYPE
     Allocation Policy" and changes the policy for RRTYPE 0xFFFF to be
     "IETF Standards Action".  Remaining instances of "IETF Consensus"
     are changed to "IETF Review", per [RFC5226].  It also specifies
     the "DNS TYPE Allocation Policy", which is based on Expert Review
     with additional provisions and restrictions, including the
     submittal of a completed copy of the template in Appendix A to
     [email protected], in most cases, and requires
     "IETF Standards Action" as modified by [RFC4020] in other cases.

     IANA shall establish a process for accepting such templates,
     selecting an Expert from those appointed to review such template
     form applications, archiving, and making available all approved
     RRTYPE allocation templates.  It is the duty of the selected
     Expert to post the formal application template to the
     [email protected] mailing list.  See Section 3.1 and
     Appendix A for more details.

  2. For OpCodes (see Section 2.2), it changes "IETF Standards Action"
     allocation requirements to add "as modified by [RFC4020]".

  3. It changes the allocation status of RCODE 0xFFFF to be "IETF
     Standards Action required".  See Section 2.3.

  4. It adds an IANA allocation policy for the AFSDB RR Subtype field,
     which requires the creation of a new registry.  See Section 3.1.4.

  5. It splits Specification Required CLASSes into data CLASSes and
     query or meta CLASSes.  See Section 3.2.







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Appendix A.  RRTYPE Allocation Template

                DNS RRTYPE PARAMETER ALLOCATION TEMPLATE

  When ready for formal consideration, this template is to be submitted
  to IANA for processing by emailing the template to
  [email protected].

  A.    Submission Date:

  B.    Submission Type:
        [ ] New RRTYPE
        [ ] Modification to existing RRTYPE

  C.    Contact Information for submitter:
           Name:
           Email Address:
           International telephone number:
           Other contact handles:

           (Note: This information will be publicly posted.)

  D.    Motivation for the new RRTYPE application?
        Please keep this part at a high level to inform the Expert and
        reviewers about uses of the RRTYPE.  Remember most reviewers
        will be DNS experts that may have limited knowledge of your
        application space.

  E.    Description of the proposed RR type.
        This description can be provided in-line in the template, as an
        attachment, or with a publicly available URL:

  F.    What existing RRTYPE or RRTYPEs come closest to filling that
        need and why are they unsatisfactory?

  G.    What mnemonic is requested for the new RRTYPE (optional)?
        Note: This can be left blank and the mnemonic decided after the
        template is accepted.

  H.    Does the requested RRTYPE make use of any existing IANA
        Registry or require the creation of a new IANA sub-registry in
        DNS Parameters?
        If so, please indicate which registry is to be used or created.
        If a new sub-registry is needed, specify the allocation policy
        for it and its initial contents.  Also include what the
        modification procedures will be.





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  I.    Does the proposal require/expect any changes in DNS
        servers/resolvers that prevent the new type from being
        processed as an unknown RRTYPE (see [RFC3597])?

  J.    Comments:

Normative References

  [RFC1034]   Mockapetris, P., "Domain names - concepts and
              facilities", STD 13, RFC 1034, November 1987.

  [RFC1035]   Mockapetris, P., "Domain names - implementation and
              specification", STD 13, RFC 1035, November 1987.

  [RFC1996]   Vixie, P., "A Mechanism for Prompt Notification of Zone
              Changes (DNS NOTIFY)", RFC 1996, August 1996.

  [RFC2136]   Vixie, P., Ed., Thomson, S., Rekhter, Y., and J. Bound,
              "Dynamic Updates in the Domain Name System (DNS UPDATE)",
              RFC 2136, April 1997.

  [RFC2181]   Elz, R. and R. Bush, "Clarifications to the DNS
              Specification", RFC 2181, July 1997.

  [RFC2671]   Vixie, P., "Extension Mechanisms for DNS (EDNS0)", RFC
              2671, August 1999.

  [RFC2845]   Vixie, P., Gudmundsson, O., Eastlake 3rd, D., and B.
              Wellington, "Secret Key Transaction Authentication for
              DNS (TSIG)", RFC 2845, May 2000.

  [RFC2930]   Eastlake 3rd, D., "Secret Key Establishment for DNS (TKEY
              RR)", RFC 2930, September 2000.

  [RFC3425]   Lawrence, D., "Obsoleting IQUERY", RFC 3425, November
              2002.

  [RFC3597]   Gustafsson, A., "Handling of Unknown DNS Resource Record
              (RR) Types", RFC 3597, September 2003.

  [RFC4020]   Kompella, K. and A. Zinin, "Early IANA Allocation of
              Standards Track Code Points", BCP 100, RFC 4020, February
              2005.

  [RFC4033]   Arends, R., Austein, R., Larson, M., Massey, D., and S.
              Rose, "DNS Security Introduction and Requirements", RFC
              4033, March 2005.




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RFC 5395                DNS IANA Considerations            November 2008


  [RFC4034]   Arends, R., Austein, R., Larson, M., Massey, D., and S.
              Rose, "Resource Records for the DNS Security Extensions",
              RFC 4034, March 2005.

  [RFC4035]   Arends, R., Austein, R., Larson, M., Massey, D., and S.
              Rose, "Protocol Modifications for the DNS Security
              Extensions", RFC 4035, March 2005.

  [RFC4635]   Eastlake 3rd, D., "HMAC SHA (Hashed Message
              Authentication Code, Secure Hash Algorithm) TSIG
              Algorithm Identifiers", RFC 4635, August 2006.

  [RFC5226]   Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

  [US-ASCII]  ANSI, "USA Standard Code for Information Interchange",
              X3.4, American National Standards Institute: New York,
              1968.

Informative References

  [Dyer1987]  Dyer, S., and F. Hsu, "Hesiod", Project Athena Technical
              Plan - Name Service, April 1987.

  [Moon1981]  Moon, D., "Chaosnet", A.I. Memo 628, Massachusetts
              Institute of Technology Artificial Intelligence
              Laboratory, June 1981.

  [RFC1183]   Everhart, C., Mamakos, L., Ullmann, R., and P.
              Mockapetris, "New DNS RR Definitions", RFC 1183, October
              1990.

  [RFC1591]   Postel, J., "Domain Name System Structure and
              Delegation", RFC 1591, March 1994.

  [RFC2606]   Eastlake 3rd, D. and A. Panitz, "Reserved Top Level DNS
              Names", BCP 32, RFC 2606, June 1999.

  [RFC2673]   Crawford, M., "Binary Labels in the Domain Name System",
              RFC 2673, August 1999.

  [RFC2929]   Eastlake 3rd, D., Brunner-Williams, E., and B. Manning,
              "Domain Name System (DNS) IANA Considerations", BCP 42,
              RFC 2929, September 2000.

  [RFC2931]   Eastlake 3rd, D., "DNS Request and Transaction Signatures
              ( SIG(0)s )", RFC 2931, September 2000.



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RFC 5395                DNS IANA Considerations            November 2008


  [RFC3363]   Bush, R., Durand, A., Fink, B., Gudmundsson, O., and T.
              Hain, "Representing Internet Protocol version 6 (IPv6)
              Addresses in the Domain Name System (DNS)", RFC 3363,
              August 2002.

  [RFC4343]   Eastlake 3rd, D., "Domain Name System (DNS) Case
              Insensitivity Clarification", RFC 4343, January 2006.

Author's Address

  Donald E. Eastlake 3rd
  Stellar Switches
  155 Beaver Street
  Milford, MA 01757 USA

  Phone: +1-508-634-2066 (h)
  EMail: [email protected]


































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