Network Working Group                                           C. Adams
Request for Comments: 3029                          Entrust Technologies
Category: Experimental                                      P. Sylvester
                                    EdelWeb SA - Groupe ON-X Consulting
                                                           M. Zolotarev
                                     Baltimore Technologies Pty Limited
                                                          R. Zuccherato
                                                   Entrust Technologies
                                                          February 2001


               Internet X.509 Public Key Infrastructure
          Data Validation and Certification Server Protocols

Status of this Memo

  This memo defines an Experimental Protocol for the Internet
  community.  It does not specify an Internet standard of any kind.
  Discussion and suggestions for improvement are requested.
  Distribution of this memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (2001).  All Rights Reserved.

Abstract

  This document describes a general Data Validation and Certification
  Server (DVCS) and the protocols to be used when communicating with
  it.  The Data Validation and Certification Server is a Trusted Third
  Party (TTP) that can be used as one component in building reliable
  non-repudiation services.

  Useful Data Validation and Certification Server responsibilities in a
  PKI are to assert the validity of signed documents, public key
  certificates, and the possession or existence of data.

  Assertions created by this protocol are called Data Validation
  Certificates (DVC).

  We give examples of how to use the Data Validation and Certification
  Server to extend the lifetime of a signature beyond key expiry or
  revocation and to query the Data Validation and Certification Server
  regarding the status of a public key certificate.  The document
  includes a complete example of a time stamping transaction.






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Table of Contents

  1. Introduction .................................................  2
  2. Services provided by DVCS ....................................  4
   2.1 Certification of Possession of Data ........................  4
   2.2 Certification of Claim of Possession of Data ...............  4
   2.3 Validation of Digitally Signed Documents ...................  4
   2.4 Validation of Public Key Certificates ......................  5
  3. Data Certification Server Usage and Scenarii .................  5
  4. Functional Requirements for DVCS .............................  7
  5. Data Certification Server Transactions .......................  7
  6. Identification of the DVCS ...................................  8
  7. Common Data Types ............................................  9
   7.1 Version ....................................................  9
   7.2 DigestInfo ................................................. 10
   7.3. Time Values ............................................... 10
   7.4. PKIStatusInfo ............................................. 11
   7.5. TargetEtcChain ............................................ 11
   7.6. DVCSRequestInformation .................................... 12
   7.7. GeneralName and GeneralNames .............................. 13
  8. Data Validation and Certification Requests ................... 13
  9. DVCS Responses ............................................... 17
   9.1. Data Validation Certificate ............................... 18
   9.2. DVCS Error Notification ................................... 21
  10. Transports .................................................. 22
   10.1 DVCS Protocol via HTTP or HTTPS ........................... 22
   10.2 DVCS Protocol Using Email ................................. 22
  11. Security Considerations ..................................... 23
  12. Patent Information .......................................... 23
  13. References .................................................. 25
  14. Authors' Addresses .......................................... 26
  APPENDIX A - PKCS #9 Attribute .................................. 27
  APPENDIX B - Signed document validation ......................... 27
  APPENDIX C - Verifying the Status of a Public Key Certificate ... 28
  Appendix D - MIME Registration .................................. 30
  Appendix E - ASN.1 Module using 1988 Syntax ..................... 31
  Appendix F - Examples ........................................... 34
  Appendix G - Acknowledgements ................................... 50
  Full Copyright Statement ........................................ 51

1. Introduction

  This document is the result of work that has been proposed and
  discussed within the IETF PKIX working group.  The authors and some
  members of the group felt that promoting the rather new concepts into
  the standards process seemed premature.  The concepts presented have
  been stable for some time and partially implemented.  It was agreed
  that a publication as experimental RFC was an appropriate means to



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  get a stable reference document to permit other implementations to
  occur.

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

  A Data Validation and Certification Server (DVCS) is a Trusted Third
  Party (TTP) providing data validation services, asserting correctness
  of digitally signed documents, validity of public key certificates,
  and possession or existence of data.

  As a result of the validation, a DVCS generates a Data Validation
  Certificate (DVC).  The data validation certificate can be used for
  constructing evidence of non-repudiation relating to the validity and
  correctness of an entity's claim to possess data, the validity and
  revocation status of an entity's public key certificate and the
  validity and correctness of a digitally signed document.

  Services provided by a DVCS do not replace the usage of CRLs and OCSP
  for public key certificate revocation checking in large open
  environments, due to concerns about the scalability of the protocol.

  It should be rather used to support non-repudiation or to supplement
  more traditional services concerning paperless document environments.
  The presence of a data validation certificate supports
  non-repudiation by providing evidence that a digitally signed
  document or public key certificate was valid at the time indicated in
  the DVC.

  A DVC validating a public key certificate can for example be used
  even after the public key certificate expires and its revocation
  information is no longer or not easily available.  Determining the
  validity of a DVC is assumed to be a simpler task, for example, if
  the population of DVCS is significantly smaller than the population
  of public key certificate owners.

  An important feature of the protocol is that DVCs can be validated by
  using the same protocol (not necessarily using the same service), and
  the validity of a signed document, in particular a DVC, can also be
  determined by means other than by verifying its signature(s), e.g.,
  by comparing against an archive.

  The production of a data validation certificate in response to a
  signed request for validation of a signed document or public key
  certificate also provides evidence that due diligence was performed
  by the requester in validating a digital signature or public key
  certificate.



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  This document defines the use of digital signatures to insure the
  authenticity of documents and DVCs, and uses a corresponding
  terminology; the use of other methods to provide evidence for
  authenticity is not excluded, in particular it is possible to replace
  a SignedData security envelope by another one.

2. Services provided by DVCS

  The current specification defines 4 types of validation and
  certification services:

  - Certification of Possession of Data (cpd),
  - Certification of Claim of Possession of Data (ccpd),
  - Validation of Digitally Signed Document (vsd), and
  - Validation of Public Key Certificates (vpkc).

  A DVCS MUST support at least a subset of these services.  A DVCS may
  support a restricted vsd service allowing to validate data validation
  certificates.

  On completion of each service, the DVCS produces a data validation
  certificate - a signed document containing the validation results and
  trustworthy time information.

2.1 Certification of Possession of Data

  The Certification of Possession of Data service provides evidence
  that the requester possessed data at the time indicated and that the
  actual data were presented to the Data Validation Server.

2.2 Certification of Claim of Possession of Data

  The Certification of Claim of Possession of Data service is similar
  to the previous one, except that the requester does not present the
  data itself but a message digest.

2.3 Validation of Digitally Signed Documents

  The Validation of Digitally Signed Document service is used when
  validity of a signed document is to be asserted.

  The DVCS verifies all signatures attached to the signed document
  using all appropriate status information and public key certificates.
  The DVCS verifies the mathematical correctness of all signatures
  attached to the document and also checks whether the signing entities
  can be trusted, for example by validating the full certification path
  from the signing entities to a trusted point (e.g., the DVCS's CA, or
  the root CA in a hierarchy).



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  The DVCS may be able to rely on relevant CRLs or may need to
  supplement this with access to more current status information from
  the CAs for example by accessing an OCSP service, a trusted directory
  service, or other DVCS services.

  The DVCS will perform verification of all signatures attached to the
  signed document.  A failure of the verification of one of the
  signatures does not necessarily result in the failure of the entire
  validation, and vice versa, a global failure may occur if the
  document has an insufficient number of signatures.

2.4 Validation of Public Key Certificates

  The Validation of Public Key Certificates service is used to verify
  and assert the validity (according to [RFC2459]) of one or more
  public key certificates at the specified time.

  When verifying a public key certificate, the DVCS verifies that the
  certificate included in the request is a valid certificate and
  determines its revocation status at a specified time.  DVS checks the
  full certification path from the certificate's issuer to a trusted
  point.  Again, the DVCS MAY be able to rely on external information
  (CRL, OCSP, DVCS).

3. Data Certification Server Usage and Scenarii.

  It is outside the scope of this document to completely describe
  different operational scenarii or usages for DVCS.

  See Appendix B and C for a set of some basic examples and use cases.

  The Validate Signed Document service can be used to support non-
  repudiation services, to allow use of the signed document beyond
  public key certificate revocation or expiry, or simply to delegate
  signature validation to a trusted central (company wide) service.

  The Validate Public Key Certificate service can be used when timely
  information regarding a certificate's revocation status is required
  (e.g., high value funds transfer or the compromise of a highly
  sensitive key) or when evidence supporting non-repudiation is
  required.

  A data validation certificate may be used to simplify the validation
  of a signature beyond the expiry or subsequent revocation of the
  signing certificate: a Data validation certificate used as an
  authenticated attribute in a signature includes an additional





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  assertion about the usability of a certificate that was used for
  signing.  In order to validate such a signature it may be sufficient
  to only validate the data validation certificate.

  A DVCS may include additional key exchange certificates in a data
  validation certificate to validate a key exchange certificate in
  order to provide to an application a set of additional authorised
  recipients for which a session key should also be encrypted.  This
  can be used for example to provide central management of a company
  wide recovery scheme.  Note, that the additional certificates may not
  only depend on the requested certificate, but also on the requester's
  identity.

  The Certification of Claim of Possession of Data service is also
  known as time stamping.

  The Certification of Possession of Data service can be used to assert
  legal deposit of documents, or to implement archival services as a
  trusted third party service.

  The Data Validation and Certification Server Protocols can be used in
  different service contexts.  Examples include company-wide
  centralised services (verification of signatures, certification of
  company certificates), services to cooperate in a multi-organization
  community, or general third party services for time stamping or data
  archival.

  An important application of DVCS is an enterprise environment where
  all security decisions are based on company wide rules.  A company
  wide DVCS service can be used to delegate all technical decisions
  (e.g., path validation, trust configuration) to a centrally managed
  service.

  In all cases, the trust that PKI entities have in the Data Validation
  and Certification Server is transferred to the contents of the Data
  Validation Certificate  (just as trust in a CA is transferred to the
  public key certificates that it issues).

  A DVCS service may be combined with or use archiving and logging
  systems, in order to serve as a strong building block in non-
  repudiation services.  In this sense it can be regarded as an
  Evidence Recording Authority [ISO-NR].









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4. Functional Requirements for DVCS

  The DVCS MUST

  1. provide a signed response in the form of a data validation
     certificate to the requester, as defined by policy, or an error
     response.  The DVCS service definition and the policy define how
     much information that has been used by the DVCS to generate the
     response will be included in a data validation certificate, e.g.,
     public key certificates, CRLs, and responses from other OCSP
     servers, DVCS, or others.

  2. indicate in the data validation certificate whether or not the
     signed document, the public key certificate(s), or the data were
     validated, and, if not, the reason why the verification failed.

  3. include a strictly monotonically increasing serial number in each
     data validation certificate.

  4. include a time of day value or a time stamp token into each data
     validation certificate.

  5. sign each data certification token using a key that has been
     certified with a dvcs signing extended key purpose, and include a
     reference to this certificate as a signed attribute in the
     signature.

  6. check the validity of its own signing key and certificate before
     delivering data validation certificates and MUST not deliver data
     validation certificate in case of failure.

  A DVCS SHOULD include within each data validation certificate a
  policy identifier to determine the trust and validation policy used
  for DVC's signature.

5. Data Certification Server Transactions

  A DVCS transaction begins with a client preparing a Data Validation
  and Certification Request.  The request always contains data for
  which validity, correctness or possession is to be certified.

  The request MAY be encapsulated using a security envelope to provide
  for authentication of both requester and server.  Requester
  authentication can be achieved by several of the formats described in
  CMS, in particular, signedData.






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  The DVCS client chooses an appropriate transport mechanism to convey
  the requests to a DVCS.  It may also be necessary to choose a
  transport mechanism providing confidentiality and, in particular,
  allowing authentication of the DVCS by the requestor, e.g., TLS or
  CMS or S/MIME encryption.

  If the request is valid, the DVCS performs all necessary
  verifications steps, and generates a Data Validation Certificate
  (DVC), and sends a response message containing the DVC back to the
  requestor.

  The Data Validation Certificate is formed as a signed document (CMS
  SignedData).

  As with the request, it may be necessary to choose a transport
  mechanism that provides for confidentiality to carry the DVC.  DVCs
  are not necessarily transported the same way as requests, e.g., they
  can be returned using e-mail after an online request received via
  HTTPS.

  If the request was invalid, the DVCS generates a response message
  containing an appropriate error notification.

  Upon receiving the response, the requesting entity SHOULD verify its
  validity, i.e., whether it contains an acceptable time, the correct
  name for the DVCS, the correct request information and message
  imprint, a valid signature, and satisfactory status, service and
  policy fields.

  When verifying the validity of a DVC, it is up to the requestor's
  application to check whether a DVCS's signing certificate is valid.
  Depending on the usage environment, different methods, online or out
  of band, e.g., CRLs, DVCS, or OCSP, may have to be used.

  After all checks have passed, the data validation certificate can be
  used to authenticate the correctness or possession of the
  corresponding data.

  A DVCS may return more than one DVC corresponding to one request.  In
  this case, all but one request have a global status of 'WAITING'.

6. Identification of the DVCS

  In order to be able to import elements from dvcs the following object
  identifier is used as a ASN.1 module identifier.

  id-mod-dvcs OBJECT IDENTIFIER ::= {iso(1) identified-organization(3)
    dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0) 15}



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  The DVCS that use SignedData to provide authentication for DVCs MUST
  sign all data certification messages with a key whose corresponding
  certificate MUST contain the extended key usage field extension as
  defined in [RFC2459] Section 4.2.1.14 with KeyPurposeID having value
  id-kp-dvcs.  This extension MUST be marked as critical.

  The Data Validation Certificate MUST contain an ESSCertID
  authenticated attribute for the certificate used by the DVCS for
  signing.

  id-kp-dvcs  OBJECT IDENTIFIER ::= {iso(1) identified-organization(3)
       dod(6) internet(1) security(5) mechanisms(5) pkix(7) kp(3) 10}

  Consistent KeyUsage bits:

  digitalSignature, nonRepudiation, keyCertSign, cRLSign

  A DVCS's certificate MAY contain an Authority Information Access
  extension [RFC2459] in order to convey the method of contacting the
  DVCS.  The accessMethod field in this extension MUST contain the OID
  id-ad-dvcs:

  id-ad-dvcs  OBJECT IDENTIFIER ::= {iso(1) identified-organization(3)
       dod(6) internet(1) security(5) mechanisms(5) pkix(7) ad(48) 4}

  The value of the 'accessLocation' field defines the transport (e.g.,
  an URI) used to access the DVCS.

7. Common Data Types

  There are several common data types that occur in the request and the
  response data structures.  These data types are either defined by
  this document or imported from other sources.  This chapter defines
  and describes these types and lists their usages.

7.1 Version:

  The request and the response include an optional integer field
  specifying the version of the data structure.  For both fields the
  value is 1, or the field is not present at all in this version of the
  protocol.










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7.2 DigestInfo:

  This element is defined in [RFC2315].  Since the status of that
  document is informational, the definition is repeated here:

  DigestInfo ::= SEQUENCE {
      digestAlgorithm   DigestAlgorithmIdentifier,
      digest            Digest }

  Digest ::= OCTET STRING

  The fields of type DigestInfo have the following meanings:

  - The field 'digestAlgorithm' identifies the message-digest algorithm
    (and any associated parameters) under which data are digested.

  - The field 'digest' is the result of the message-digesting process.

  A DigestInfo is used in two places:

  - as a data portion for the ccpd service, and

  - in all a data validation certificates to hold a digest of the data
    portion of the corresponding request or a copy of the data field
    for a ccpd service.

7.3. Time Values

  Indicators of time can be present in requests and responses.  In the
  most simple form, the time is represented as GeneralizedTime where
  fractions of seconds are allowed.

  An alternate form is a timeStampToken from a TSA, or as a DVC (or
  some other token) from another third party service.

  It is a matter of policy whether a DVCS tries to interpret or
  validate a Time Value in a request.

  DVCSTime ::= CHOICE  {
       genTime                      GeneralizedTime,
       timeStampToken               ContentInfo }

  Future versions of the protocol MAY include additional time formats.

  Time values generated by the DVCS are increasing but not necessarily
  unique, an order among DVCs is defined by serial numbers.





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7.4. PKIStatusInfo

  This structure is defined in [RFC2510].  It is used as component of
  the 'chain' field of a TargetEtcChain structure, and as a global
  status indicator in the DVCSResponse structure.  Every occurrence of
  PKIStatusInfo is generated by the responding DVCS to reflect the
  result of some local verification.

7.5. TargetEtcChain

  A TargetEtcChain structure contains certificates and other indicators
  to describe either (in a request for a cpkc service) information to
  be validated, or the result of the verifications.  The structure may
  also contain information about policies and policy mappings.

  The details about how to fill in and to interpret the structure are
  defined later for each service.

  The 'pathProcInput' field contains information about policies and
  policy mapping to be used or used during a validation.

  In a response, the 'pkistatus' and `certstatus' choices can only
  occur in the 'chain' sequence.  If present, they contain the result
  of a local verification of the immediately preceding element, or of
  the target value, if it is the first element in the 'chain' sequence.
  If no 'pkistatus' or 'certstatus' is present, the DVCS considers all
  elements in the 'chain' as trustworthy.  Note, that there may be a
  valid OCSP response or DVC indicating an invalid certificate.

  TargetEtcChain ::= SEQUENCE {
       target                       CertEtcToken,
       chain                        SEQUENCE SIZE (1..MAX) OF
                                       CertEtcToken OPTIONAL,
       pathProcInput                [0] PathProcInput OPTIONAL }

  PathProcInput ::= SEQUENCE {
       acceptablePolicySet          SEQUENCE SIZE (1..MAX) OF
                                       PolicyInformation,
       inhibitPolicyMapping         BOOLEAN DEFAULT FALSE,
       explicitPolicyReqd           BOOLEAN DEFAULT FALSE }

  CertEtcToken ::= CHOICE {

       certificate                  [0] IMPLICIT Certificate ,
       esscertid                    [1] ESSCertId ,
       pkistatus                    [2] IMPLICIT PKIStatusInfo ,
       assertion                    [3] ContentInfo ,
       crl                          [4] IMPLICIT CertificateList,



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       ocspcertstatus               [5] IMPLICIT CertStatus,
       oscpcertid                   [6] IMPLICIT CertId ,
       oscpresponse                 [7] IMPLICIT OCSPResponse,
       capabilities                 [8] SMIMECapabilities,
       extension                    Extension }

  Certificate, PolicyInformation and CertificateList are defined in
  [RFC2459].  ESSCertId is defined in [RFC2634].  CertId, OCSPResponse
  and CertStatus are defined in [RFC2560].  PKIStatusField is defined
  in [RFC2510].

  The choice 'assertion' can contain a data validation certificate, or
  a timeStamp, or other assertions.

  The choices 'assertion', 'ocspresponse' and 'crl' are provided by
  services external to the responding DVCS.  The choices 'certStatus'
  and 'pkistatus' reflect decisions made directly by the responding
  DVCS.

  As a replacement for certificates, certification identifiers
  (ESSCertId, CertId)  MAY be used in requests and responses, if this
  is sufficient to perform the service, e.g., when the corresponding
  certificates are provided elsewhere in a request or response (as part
  of the SignedData type).

  Certificate or certification identifiers of certification authorities
  MAY occur in any order and MAY represent several certification
  chains.

  The choice 'capabilities' can be used to indicate SMIMECapabilities.
  It applies to the certificate identified by the preceding element in
  the sequence.

7.6. DVCSRequestInformation

  A DVCSRequestInformation data structure contains general information
  about the Data Validation and Certification Request.  This structure
  occurs in a request, and is also included in a corresponding Data
  Validation Certificate.

  DVCSRequestInformation ::= SEQUENCE  {

          version                      INTEGER DEFAULT 1 ,
          service                      ServiceType,
          nonce                        INTEGER OPTIONAL,
          requestTime                  DVCSTime OPTIONAL,
          requester                    [0] GeneralNames OPTIONAL,
          requestPolicy                [1] PolicyInformation OPTIONAL,



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          dvcs                         [2] GeneralNames OPTIONAL,
          dataLocations                [3] GeneralNames OPTIONAL,
          extensions                   [4] IMPLICIT Extensions OPTIONAL
  }

  The ServiceType type enumerates the DVCS service type of a request.
  See chapter 2 for the description of the services.

  ServiceType ::= ENUMERATED { cpd(1), vsd(2), cpkc(3), ccpd(4) }

7.7. GeneralName and GeneralNames

  There are several occurrences of SEQUENCES of GeneralName and
  GeneralNames.  These structures are imported from [RFC2459].

8. Data Validation and Certification Requests

  A Data Validation and Certification request is a ContentInfo defined
  in [RFC2630].

  It may consist of a [RFC2630] content with a contenttype id-ct-
  DVCSRequestData signalling a DVCSRequestData,

  id-ct-DVCSRequestData OBJECT IDENTIFIER ::= {iso(1) member-body(2)
    us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) ct(1) 7}

  These data are optionally encapsulated by contenttypes that provide
  for authentication and/or confidentiality.

  This document describes the usage of a SignedData construct of
  [RFC2630] where the contenttype indicated in the eContentType of the
  encapContentInfo is id-ct-DVCSRequestData and the eContent of the
  encapContentInfo, carried as an octet string, contains a
  DVCSRequestData structure.

  When using a SignedData structure, a Data Validation and
  Certification Request MAY contain several SignerInfo structures, and
  countersignature attributes depending on operational environments.
  When an end user client creates the request, there is one or zero
  SignerInfo.  A relaying DVCS MAY add an additional signature or a
  countersignature attribute, or MAY use another encapsulation from
  [RFC2630] that provides for authentication and/or confidentiality.

  The content of a request consists of a description of the desired
  service and additional parameters, the data to be validated, and an
  optional identifier of the request.





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  DVCSRequest ::= SEQUENCE  {
      requestInformation         DVCSRequestInformation,
      data                       Data,
      transactionIdentifier      GeneralName OPTIONAL
  }

  The 'DVCSRequest.requestInformation' element contains general
  information about the request.  It is filled in by the requester as
  follows:

  - The 'version' field is set to 1 or the field is absent in this
    version of the protocol.

    The field 'service' contains the requested service.

  - The 'nonce' field MAY be used to provide additional protection
    against replay or content guessing attacks.

  - The 'requestTime' field MAY be used to indicate the time for which
    the requested service should be performed.  For a vsd and cpkc
    service, it specifies the time for which the validity of a signed
    document or certicates is to be asserted.  For the other service,
    the field is ignored by the DVCS.  If the field is absent, the
    current time is assumed.

  - The value of the 'requester' field indicates the requesting entity.

    The interpretation and usage of this field MUST be defined by the
    DVCS policy.

    Some usage examples are:

    If the field is present, and the request is signed, a DVCS MAY
    require that the field MUST match the identity (subjectName or
    subjectAltName extension) of the corresponding signature
    certificate.

    A request MAY be signed by a DVCS when relaying it to another DVCS.

    When acting as a relay, a DVCS MAY add its own identity in the
    request relayed to another service provider, and it MAY remove the
    initial value.

  - The 'requestPolicy' field SHOULD indicate the policy under which
    the validation is requested.  This field MUST be checked by the
    DVCS to verify agreement with its own policy.  The absence of this
    field indicates that any policy is acceptable.




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  - The 'dvcs' field MAY be used to indicate a list of DVCS which can
    be contacted to provide (additional) information or to perform
    additional operations necessary to produce the response.

    It is up to the DVCS policy whether to honor this field or not, and
    to define which choice of a general name is acceptable (e.g., an
    URL or a DN).

  - The 'dataLocations' field MAY be used to indicate where a copy of
    the 'data' field of the request or supplementary information can be
    obtained.  The DVCS does not use this field for its own operation,
    the exact interpretation of this field is defined by applications.

  - The 'requestTime' field MAY be used to indicate the time for which
    the requested service should be performed.  For a vsd and cpkc
    service, it specifies the time for which the validity of a signed
    document or certicates is to be asserted.  For the other service,
    the field is ignored by the DVCS.  If the field is absent, the
    current time is assumed.  The DVCS service may have a time limit or
    a delta time limit regarding current time which are specified in
    the local policy of the DVCS service.

  - The 'extensions' field MAY be used to include additional
    information.  Extensions may be marked critical or not in order to
    indicate whether the DVCS is supposed to understand them.  This
    document does not define extensions.

  The DVCSRequest.data contains service-specific content, defined by
  each particular service provided by the DVCS.

  Depending on the requested service type, the field may contain a
  signed document, a list of certificates, a message digest or
  arbitrary data.

  The following type is used:

  Data ::= CHOICE {
        message           OCTET STRING ,
        messageImprint    DigestInfo,
        certs             SEQUENCE SIZE (1..MAX) OF
                              TargetEtcChain
  }

  The requester fills the 'data' element as follows:

  - For a vsd service request, the requestor encapsulates a CMS
    SignedData object in the value octets of the 'message' choice.




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    It is up to the requester to decide whether and how to provide any
    certificate that may be needed to verify the signature(s) in the
    signedData object.  A requester MAY add certificates to the
    encapsulated signedData object or in the certificate list of the
    request.

  - For a cpkc service request the 'certs' choice is used.

    Each certificate to be verified MUST be included in a separate
    instance of TargetEtcChain.  The 'TargetEtcChain.chain' field, if
    present, indicates one or more chains of trust that can be used to
    validate the certificate.  The DVCS MAY choose to select a subset
    of certificates as certification path, or to ignore this field.
    The 'TargetEtcChain.pathProcInput' field, if present, indicates the
    acceptable policy set and initial settings for explicit-policy-
    indicator and inhibit-policy-mapping indicators to be used in X.509
    public key certificate path validation (see [RFC2459]).

    Only the Certificate, ESSCertId, CertId or Extension choices of the
    TargetEtcChain can be used in the request.

    The requester is responsible for providing sufficient information
    to the DVCS to identify the corresponding certificates.

  - For a ccpd service the 'messageImprint' choice is used.

    The hash algorithm indicated in the hashAlgorithm field SHOULD be a
    "strong" hash algorithm (that is, it SHOULD be one-way and
    collision resistant).  It is up to the Data Certification Server to
    decide whether or not the given hash algorithm is sufficiently
    "strong" (based on the current state of knowledge in cryptanalysis
    and the current state of the art in computational resources, for
    example).

  - For a cpd service the 'message' choice is used.

    The field contains requester-specific data with any type of
    content.  The DVCS does not inspect, modify, or take any particular
    action based on the particular content of the 'message' field.

  The field 'DVCSRequest.transactionIdentifier' MAY be used in order to
  associate DVCS responses containing error messages, to requests.  For
  example, in a mail based environment, the parameter could be a copy
  of a messageid.  Note, that the transactionIdentifier is not
  necessary for associating a request with a valid data validation
  certificate.





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9. DVCS Responses

  This chapters describes the data structures that are created by a
  DVCS to indicate the results of validation and certification
  requests.

  A DVCS Response structure is generated by the DVCS as a result of
  processing of the data validation and certification request.

  A Data Validation response contains an [RFC2630] ContentInfo with a
  type of id-ct-DVCSResponseData signalling a DVCSResponse structure.

  id-ct-DVCSResponseData OBJECT IDENTIFIER ::= { iso(1) member-body(2)
      us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) ct(1) 8 }

  The data MAY be encapsulated by constructs of [RFC2630] in order to
  provide authentication of the DVCS, and or integrity and
  confidentiality of the request.  This document specifies the usage of
  a SignedData construct of [RFC2630].

  The contenttype indicated in the eContentType of the encapContentInfo
  is of type id-ct-DVCSResponseData, signalling a DVCSResponse as
  eContent of the encapContentInfo (carried as an octet string).  The
  DVCS SHOULD use a key for which a corresponding certificate indicates
  in an extendedKeyUsage the purpose of DVCS signing.

  In a critical situation when a DVCS cannot produce a valid signature
  (if the DVCS's signing key is known to be compromised, for example),
  the DVCSResponse, containing the error notification, MUST be
  generated as a signedData with no signerInfo attached.  Receiving
  unsigned DVCSResponse MUST be treated by the clients as a critical
  and fatal error, and the content of the message should not be
  implicitly trusted.

  A valid response can contain one of the following:

  1. A Data Validation Certificate (DVC), delivering the results of
     data validation operations, performed by the DVCS.

  2. An error notification.  This may happen when a request fails due
     to a parsing error, requester authentication failure, or anything
     else that prevented the DVCS from executing the request.









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  The following type is used:

  DVCSResponse ::= CHOICE {
      dvCertInfo         DVCSCertInfo ,
      dvErrorNote        [0] DVCSErrorNotice }

9.1. Data Validation Certificate

  A Data Validation Certificate is a signedData object containing a
  DVCSResponse with a 'dvCertInfo' choice.

  DVCSCertInfo::= SEQUENCE  {
           version             Integer DEFAULT 1 ,
           dvReqInfo           DVCSRequestInformation,
           messageImprint      DigestInfo,
           serialNumber        Integer,
           responseTime        DVCSTime,
           dvStatus            [0] PKIStatusInfo OPTIONAL,
           policy              [1] PolicyInformation OPTIONAL,
           reqSignature        [2] SignerInfos  OPTIONAL,
           certs               [3] SEQUENCE SIZE (1..MAX) OF
                                   TargetEtcChain OPTIONAL,
           extensions          Extensions OPTIONAL }

  The DVCSCertInfo structure is returned as a result of successful
  execution of data validation service.  It contains the results of the
  data validation, a reference to the original request, and other
  parameters.  Please note that 'successful execution' does not
  necessarily mean that the validation itself was successful - a
  DVCSCertInfo may contain both the 'valid' and 'invalid' results.

  The DVCS creates a DVCSCertInfo as follows:

  - The 'version' field is never present in this version of the
    protocol.

    The 'dvReqInfo' is essentially a copy of the 'requestInformation'
    field of the corresponding request.  The DVCS MAY modify the fields
    'dvcs', 'requester', 'dataLocations', and 'nonce' of the ReqInfo
    structure, e.g., if the request was processed by a chain of DVCS,
    if the request needs to indicate DVCS, or to indicate where to find
    a copy of the data from a 'vpd' request.  The only modification
    allowed to a 'nonce' is the inclusion of a new field if it was not
    present, or to concatenate other data to the end (right) of an
    existing value.






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  - The 'DVCSCertInfo.messageImprint' field is computed from the 'data'
    field of the corresponding request as follows:

    For the 'certs' choice (the 'vpkc' service), the digest is computed
    over the DER encoded data value.  For a 'message' choice (the 'vsd'
    and the 'vpd' services) the digest is computed over the value
    octets (not including tag and length octets) of the OCTET STRING.
    It is up to the DVCS to choose an appropriate digest algorithm.

    For a 'messageImprint' choice (the 'vcpd' service), the
    'messageImprint' of the DVCSRequest is copied as is.

  - The 'DVCSCertInfo.serialNumber' field contains a unique identifier
    of the request.

  - The field 'responseTime' indicates a time value associated with the
    response.  The value MAY be a locally generated one, or a signed
    TimeStampToken (TST) or DVC obtained from an external service.
    Before using a value obtained from an external service, the DVCS
    must validate it according the rules of the external service.

  - The field 'DVCSCertInfo.dvStatus' reflects a collective result of
    the validation.

    If the field is missing, it is an equivalent of the SUCCESS
    status.

    For a vkpc, if the status field is present and set to SUCCESS, it
    indicates that all certificates were successfully validated.  If it
    is present and set to FAILED, it indicates that all or some of the
    certificates failed validation, and the specific status of the
    'certs' should be investigated, at least one of the elements of the
    'certs' TargetEtcChain structures MUST have a failure status.

    If the field 'dvStatus' does not indicate success ('granted' or
    'granted with mods') the element 'failInfo' MAY indicate the reason
    for the failure.  Note that the field 'certs' MAY contain
    additional information about verification failures.

    A failure of the verification of one of the signatures does not
    necessarily result in failing to validate a signed document.  For
    example, as long as a sufficient number of signature was
    successfully verified, a DVC with status 'grantedWithMods' may be
    produced.  A DVC with status 'granted' MUST only be produced if all
    signatures verified successfully.






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    The field MUST be present, and the status must be set to WAITING,
    if no final response can be immediately available.  It is assumed
    that the DVCS provides an additional final status some time later.
    The details of the necessary procedures are part of the DVCS
    policy.

    In case of failure, the requester can further investigate the cause
    of the failure, by looking into the TargetEtcChain fields.
    'CertEtctoken.pkistatus' fields will indicate which item(s) has
    failed or succeeded the validation and for what reason.

  - The 'DVCSCertInfo.policy' field indicates the policy under which
    the DVCS operates.

  - If present, 'DVCSCertInfo.reqSignature' MUST be the same value as
    the signerInfos field of the corresponding request.  It is a policy
    decision whether to include this field.

  - The 'DVCSCertInfo.certs' field contains the results of the
    verifications made by the DVCS.  For the cpkc service, each element
    contains a copy of a corresponding field of the request with the
    selected subset in the targetAndChain subfield and the results of
    the verifications, and additional certificates or certificate
    references, e.g., from certification authorities or as described in
    appendix C.3.  For a vsd service, each element contains the result
    of the validation of one signature of the signed document to be
    validated.

    In case of a global status of WAITING, the DVCS MAY choose to
    return an individual status of waiting in some of the 'certs'
    field, or not to return such a TargetEtcChain at all.

    The 'acceptablePolicySet' sequence indicates the policies and
    mappings that were processed during X.509 public key certificate
    path validation.  PolicyMappingsSyntax is defined in [RFC2459].

  - The 'extensions' field MAY be used to return additional information
    to the client.  Extensions MAY be marked critical or not in order
    to indicate whether the client MUST understand them.  This document
    does not define extensions.











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9.2. DVCS Error Notification

  A DVCS Error Notification is a CMS signedData object containing a
  DVCSResponse with a 'dvErrorNote' choice.

  DVCSErrorNotice ::= SEQUENCE {
      transactionStatus           PKIStatusInfo ,
      transactionIdentifier       GeneralName OPTIONAL }

  The PKIStatusInfo is defined in [RFC2511].  For the purposes of
  communicating the DVCSErrorNotice, the following subset of
  PKIFailureInfo values is used:

  PKIFailureInfo ::= BITSTRING  {

       badRequest       (2),
       -- transaction not permitted or supported
       badTime          (3),
       -- messageTime was not sufficiently close to the system time,
       -- as defined by local policy
       badDataFormat    (5),
       -- the data submitted has the wrong format
       wrongAuthority   (6),
       -- the DVCS indicated in the request is different from the
       -- one creating the response token
       incorrectData    (7)
       --the requester's data (i.e., signature) is incorrect )

  In the DVCSErrorNotice, the PKIStatus field of the PKIStatusInfo must
  be set to REJECTED.

  The 'statusString' field of PKIStatusInfo can be used to accommodate
  extra text, such as a reason for the failure, for example "I have
  gone out of service".  The DVCS initializes the
  'DVCSErrorNotice.transactionIdentifier' with a copy of the
  'DVCSRequest.transactionIdentifier' field of the corresponding
  request.

  In certain circumstances, a DVCS may not be able to produce a valid
  response to a request (for example, if it is unable to compute
  signatures for a period of time).  In these situations the DVCS MAY
  create a response with an DVCSErrorNotice but no signature.

  DVCS clients SHOULD NOT trust unsigned responses.  A DVCS client MAY
  trust unsigned responses, if the communication channel provides for
  server authentication (e.g., by services defined by TLS [RFC2246]).





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10.  Transports

  There is no mandatory transport mechanism in this document.  All
  mechanisms are optional.  Two examples of transport protocols are
  given which allow online exchange of request and a response, and
  asynchronous communication between a client and a DVCS.

  A DVCS MAY use a combination of protocols, for example in order to
  return additional DVCs.

10.1 DVCS Protocol via HTTP or HTTPS

  This subsection specifies a means for conveying ASN.1-encoded
  messages for the DVCS protocol exchanges via the HyperText Transfer
  Protocol.

  The DER encoded DVCS requests and responses are encapsulated using a
  simple MIME object with Content-Type application/dvcs (and with the
  default binary encoding).

  This MIME object can be sent and received using common HTTP or HTTPS
  processing engines over WWW links and provides a simple client-server
  transport for DVCS messages.

10.2 DVCS Protocol Using Email

  This section specifies a means for conveying ASN.1-encoded messages
  for the protocol exchanges described in Section 8 via Internet mail.

  The DER encoded DVCS requests and responses are encapsulated using a
  simple MIME object with Content-Type application/dvcs with an
  appropriate Content-Transfer-Encoding.

  This MIME object can be sent and received using MIME processing
  engines and provides a simple Internet mail transport for DVCS
  messages.

  In order to be able to associate a possible error response with a
  request, the requester SHOULD use the field 'transactionIdentifier'.
  The requester SHOULD not make any assumption about the usage of
  message header fields by the responding service, in particular the
  usage of fields like Subject, Message-ID or References.









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11.  Security Considerations

  This entire chapter discusses security considerations.

  When designing a data validation and certification service, the
  following considerations have been identified that have an impact
  upon the validity or "trust" in the data validation certificate.

  It is imperative that keys used to sign DVCs are guarded with proper
  security and controls in order to minimize the possibility of
  compromise.  Nevertheless, in case the private key does become
  compromised, an audit trail of all the DVC generated by the DVCS
  SHOULD be kept as a means to help discriminate between genuine and
  false DVCs.  A DVCS MAY provide for a vsd service to validate DVCs
  created by this DVCS or another one solely based on the audit trail.

  When confidentiality and server authentication is required, requests
  and responses MAY be protected using appropriate mechanisms (e.g.,
  CMS encapsulation [RFC 2630] or TLS [RFC2246]).

  Server authentication is highly recommended for the vsd and cpd
  service.

  Client identification and authentication MAY use services defined by
  TLS [RFC2246]) instead of, or in addition to, using a CMS format
  providing authentication.

12.  Patent Information

  The following United States Patents related to data validation and
  certification services, listed in chronological order, are known by
  the authors to exist at this time.  This may not be an exhaustive
  list.  Other patents may exist or be issued at any time.
  Implementers of the DVCS protocol and applications using the protocol
  SHOULD perform their own patent search and determine whether or not
  any encumberences exist on their implementation.

# 4,309,569     Method of Providing Digital Signatures
(issued) January 5, 1982
(inventor) Ralph C.  Merkle
(assignee) The Board of Trustees of the Leland Stanford Junior
University

# 5,001,752     Public/Key Date-Time Notary Facility
(issued) March 19, 1991
(inventor) Addison M.  Fischer





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# 5,022,080     Electronic Notary
(issued) June 4, 1991
(inventors) Robert T.  Durst, Kevin D.  Hunter

# 5,136,643     Public/Key Date-Time Notary Facility
(issued) August 4, 1992
(inventor) Addison M.  Fischer
(Note: This is a continuation of patent # 5,001,752.)

# 5,136,646     Digital Document Time-Stamping with Catenate Certificate
(issued) August 4, 1992
(inventors) Stuart A.  Haber, Wakefield S.  Stornetta Jr.
(assignee) Bell Communications Research, Inc.,

# 5,136,647     Method for Secure Time-Stamping of Digital Documents
(issued) August 4, 1992
(inventors) Stuart A.  Haber, Wakefield S.  Stornetta Jr.
(assignee) Bell Communications Research, Inc.,

# 5,373,561     Method of Extending the Validity of a Cryptographic
Certificate
(issued) December 13, 1994
(inventors) Stuart A.  Haber, Wakefield S.  Stornetta Jr.
(assignee) Bell Communications Research, Inc.,

# 5,422,95 Personal Date/Time Notary Device
(issued) June 6, 1995
(inventor) Addison M.  Fischer

# 5,781,629     Digital Document Authentication System
(issued) July 14, 1998
(inventor) Stuart A. Haber, Wakefield S. Stornetta Jr.
(assignee) Surety Technologies, Inc.,


















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13.  References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

  [RFC2510]  Adams, C. and S. Farrell, "Internet X.509 Public Key
             Infrastructure, Certificate Management Protocols", RFC
             2510, March 1999.

  [RFC2459]  Housley, R., Ford, W., Polk, W. and D. Solo, "Internet
             X.509 Public Key Infrastructure, Certificate and CRL
             Profile", RFC 2459, January 1999.

  [RFC2630]  Housley, R., "Cryptographic Message Syntax", RFC 2630,
             June 1999.

  [ISONR]    ISO/IEC 10181-5:  Security Frameworks in Open Systems.
             Non-Repudiation Framework.

  [RFC2119]  Bradner, S., "Key works for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

  [RFC2511]  Myers, M., Adams, C., Solo, D. and D. Kemp, "Internet
             X.509 Certificate Request Message Format", RFC 2511, March
             1999.

  [RFC2246]  Dierks, T. and C. Allen, "The TLS Protocol, Version 1.0",
             RFC 2246, January 1999.

  [RFC2634]  Hoffman P., "Enhanced Security Services for S/MIME", RFC
             2634, June 1999.

  [RFC2560]  Myers, M., Ankney, R., Malpani, A., Galperin, S. and C.
             Adams, "X.509 Internet Public Key Infrastructure Online
             Certificate Status Protocol", RFC 2560, June 1999.
















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14.  Authors' Addresses

  Carlisle Adams
  Entrust Technologies
  1000 Innovation Drive
  Ottawa, Ontario
  K2K 3E7
  CANADA

  EMail: [email protected]


  Michael Zolotarev
  Baltimore Technologies Pty Limited
  5th Floor, 1 James Place
  North Sydney, NSW 2060
  AUSTRALIA

  EMail: [email protected]


  Peter Sylvester
  EdelWeb SA - Groupe ON-X Consulting
  15, Quai de Dion Bouton
  F-92816 Puteaux Cedex
  FRANCE

  EMail: [email protected]


  Robert Zuccherato
  Entrust Technologies
  1000 Innovation Drive
  Ottawa, Ontario
  K2K 3E7
  CANADA

  EMail: [email protected]













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APPENDIX A - PKCS #9 Attribute

  We define a PKCS #9 [PKCS9] attribute type.  The attribute type has
  ASN.1 type SignedData and contains a data validation certificate.

  The object identifier id-aa-dvcs-dvc identifies the data validation
  certificate attribute type.

  id-aa-dvcs-dvc OBJECT IDENTIFIER ::= {iso(1) member-body(2)
      us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) aa(2) 29}

  The attribute may be used as an authenticated or unauthenticated
  attribute in CMS SignedData documents.

APPENDIX B - Signed document validation.

  We present some examples of a possible use of DVCS in the context of
  validation of signed documents.

B.1 Signed document validation

  The example covers the case where a DVCS is used by a signer to
  obtain a proof that a document's structure, including one or more
  attached signatures, is/was correct, after the document was signed.

  The DVC can be produced either by a DVCS that is trusted by the
  signer, or by a DVCS that is trusted by an intended verifier of the
  document.

  The signer uses the obtained DVC as an evidence that its intentions
  were good and it produced a signed document using the
  environment(keys, algorithms, etc) that was known to be OK.

  It produces a stand-alone document that can be used to extend the
  life of a signature.  This example assumes that we have total trust
  in the Data Validation and Certification Server.

  Signature algorithms and keys have a finite lifetime.  Therefore,
  signatures have a finite lifetime.  The Data Certification Server can
  be used to extend the lifetime of a signature.

  In order to extend the lifetime of a signature in this way, the
  following technique can be used:

  1) The signature needs to be certified:

     The signed message is presented to the Data Validation and
     Certification Server in a 'vsd' service request.



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     The DVCS verifies that the signature and certificates are valid at
     that time by checking expiry dates, status information, or DVCs,
     and returns a DVC.

  2) The DVC SHOULD be verified.

     The signature of the Data Validation and Certification Server in
     data certification token SHALL be verified using the Data
     Certification Server's valid verification key.

  A signer's signing key (and therefore, its signature) is only valid
  until some specified time T1.  The DVCS's signing key (and therefore,
  its signature) is valid until some specified time T2 that is
  (usually) after time T1.  Without certification, the signer's
  signature would only be valid until time T1.  With certification, the
  signer's signature remains valid until time T2, regardless of
  subsequent revocation or expiry at time T1.

  If the signature of the DVCS is valid, the trust we have in the DVCS
  allows us to conclude that the original signature on the data was
  valid at the time included in the DVC.

  The DVCS signing key MUST be of a sufficient length to allow for a
  sufficiently long lifetime.  Even if this is done, the key will have
  a finite lifetime.  Since data validation certificates are just
  another type of signed documents, they can be validated using
  (another) DVCS.

APPENDIX C - Verifying the Status of a Public Key Certificate

  We now present three examples of how to produce a data validation
  certificate that can be used to assert that a public key certificate
  is valid, trusted, and can be used for a particular purpose.

  A client wants to use a given public key certificate either to use it
  to verify a signature on a document or to use it for document
  encryption.

  A DVCS MUST have access to current information regarding public
  certificate status, it can therefore be used to verify the revocation
  status of a certificate at the current time.

  The following technique can be used:

  A) The public key certificate needs to be validated.

     The certificate is presented to the Data Certification Server
     using a 'vpkc' service.



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     The Data Validation and Certification Server verifies that the
     public key certificate is valid and that it hasn't been revoked
     and then returns a data validation certificate.

  B) The data validation certificate MUST be verified.

     The signature of the Data Certification Server in the data
     certification token SHALL be verified using the Data Validation
     and Certification Server's valid certificate.

  C) The public key certificate is used:

  C.1) A clients's own public key certificate (i.e., the corresponding
       private key) can be used to add a signature to a document.  The
       signing certificate and the data validation certificate can be
       added as signed attributes to the signature.

       A data validation certificate can now be used during the
       validation signatures using the key contained in the public key
       certificate.  This service provided by the DVCS can be thought
       of as a supplement to the usual method of checking revocation
       status.

       In other words, signature validation at a later time does not
       necessarily require access to the revocation status of the
       user's signing certificate, access to a DVCS service and
       validation of the DVC is sufficient to verify a signature.  Note
       that the DVC does not tell when the signature had been created,
       it only indicates when the signing certificate was valid.

  C.2) A public key certificate for key exchange can be used after
       having obtained a data validation certification certificate to
       encrypt data.  The DVC can be stored with the data and/or stored
       by the creator of the encrypted document.

       If an intended recipient of the document claims that the creator
       did not use an appropriate encryption key, the DVC (obtained by
       a recipient's DVCS) can be used as evidence that the recipient's
       DVCS has authorized the usage of the public key.

  C.3) The procedure described in the previous paragraph can be
       enhanced to provide domain encryption in several ways.
       Organizations require that encrypted documents need to be
       recoverable.  One simple way is to always encrypt documents with
       additional recipients that act as 'domain encryption centers' or
       'recovery centers'.  This is not a technically difficult





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       problem, but may require complicated and difficult interactions
       with the end user, in particular when the document's recipients
       are in several different organizations.

       One possible solution consists of adding additional certificates
       to the dvc that validates the usage of a particular public key
       certificate used for encryption.  In an environment of several
       organizations, one of the possible procedures may be:

       The client asks its local dvcs to validate the public key
       certificate.  The dvcs forwards the request to a dvcs of a
       remote organization.  The remotes organization's dvcs verifies
       the certificate and provides a dvc assertion validating the
       certificate.  It adds additional certificates usable for key
       exchange to the certEtcChain structure indicating additional
       required recipients.  The local dvc creates a dvc containing the
       dvc of the remote dvcs.  It may add additional certificates or
       references to the dvc.  The clients use all validated
       certificates to be usable for key exchange to enhance its list
       of recipients.

       In the local dvcs may as well use local information about the
       remote organization's need for additional recipients.

Appendix D - MIME Registration

  To: [email protected] Subject: Registration of MIME media type
  application/timestamp

  MIME media type name: application

  MIME subtype name: dvcs

  Required parameters: None

  Optional parameters: None

  Encoding considerations: binary or Base64

  Security considerations: Carries a request for a data validation and
  certification service and the response.  A request may be
  cryptographically signed.  The response will be cryptographically
  signed.

  Interoperability considerations: None

  Published specification:
  RFC 3029 on Data Validation and Certification Server Protocols



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  Applications which use this media type: Data Validation and
  Certification Servers and Clients

  Additional information:

    Magic number(s): None
    File extension(s): .dvc
    Macintosh File Type Code(s): none

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

  Intended usage: COMMON

  Author/Change controller: Peter Sylvester
  <[email protected]>

Appendix E - ASN.1 Module using 1988 Syntax

PKIXDVCS {iso(1) identified-organization(3) dod(6) internet(1)
  security(5) mechanisms(5) pkix(7) id-mod(0) id-mod-dvcs(15)}

DEFINITIONS IMPLICIT TAGS ::=

BEGIN

-- EXPORTS ALL --

IMPORTS
 Extensions, AlgorithmIdentifier
 FROM PKIX1Explicit88 {iso(1) identified-organization(3)
 dod(6) internet(1) security(5) mechanisms(5) pkix(7)
 id-mod(0) id-pkix1-explicit-88(1)}

 GeneralName, PolicyInformation
 FROM PKIX1Implicit88 {iso(1) identified-organization(3)
 dod(6) internet(1) security(5) mechanisms(5) pkix(7)
 id-mod(0) id-pkix1-implicit-88(2)}

 PKIStatusInfo, PKIStatusField FROM PKIXCMP {iso(1)
 identified-organization(3) dod(6) internet(1) security(5)
 mechanisms(5) pkix(7) id-mod(0)
 id-mod-cmp(9)}

 ContentInfo FROM CryptographicMessageSyntax {iso(1)
 member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
 smime(16) modules(0) cms(1)}




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 ESSCertID FROM ExtendedSecurityServices
 { iso(1) member-body(2) us(840) rsadsi(113549)
 pkcs(1) pkcs-9(9) smime(16) modules(0) ess(2) }

 CertId, OCSPResponse, CertStatus
 FROM OCSP
 {iso(1) identified-organization(3)
 dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)
 id-mod-ocsp(14)}

 SMIMECapabilities FROM SecureMimeMessageV3
 { iso(1) member-body(2) us(840) rsadsi(113549)
  pkcs(1) pkcs-9(9) smime(16) modules(0) smime(4) }

 ;

-- Authority Information Access for DVCS

id-ad-dvcs  OBJECT IDENTIFIER ::= {id-pkix id-ad(48) 4}

-- Key Purpose for DVCS

id-kp-dvcs  OBJECT IDENTIFIER ::= {id-pkix id-kp(3) 10}

-- eContentType for a dvcs requests and responses

id-ct-DVCSRequestData  OBJECT IDENTIFIER ::= { id-smime ct(1) 7 }
id-ct-DVCSResponseData OBJECT IDENTIFIER ::= { id-smime ct(1) 8 }

-- Data validation certificate attribute

id-aa-dvcs-dvc OBJECT IDENTIFIER ::= { id-smime aa(2) 29 }

-- using the following bases :

id-pkix     OBJECT IDENTIFIER ::= {iso(1)
              identified-organization(3) dod(6)
              internet(1) security(5) mechanisms(5) pkix(7)}

id-smime    OBJECT IDENTIFIER ::= { iso(1) member-body(2)
              us(840) rsadsi(113549) pkcs(1) pkcs-9(9) 16 }

Version ::= Integer

DigestInfo ::= SEQUENCE {
   digestAlgorithm   DigestAlgorithmIdentifier,
   digest            Digest
}



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Digest ::= OCTET STRING

Nonce ::= Integer

DVCSTime ::= CHOICE  {
    genTime                      GeneralizedTime,
    timeStampToken               ContentInfo
}
TargetEtcChain ::= SEQUENCE {
    target                       CertEtcToken,
    chain                        SEQUENCE SIZE (1..MAX) OF
                                    CertEtcToken OPTIONAL,
    pathProcInput                [0] PathProcInput OPTIONAL
}

PathProcInput ::= SEQUENCE {
    acceptablePolicySet          SEQUENCE SIZE (1..MAX) OF
                                    PolicyInformation,
    inhibitPolicyMapping         BOOLEAN DEFAULT FALSE,
    explicitPolicyReqd           BOOLEAN DEFAULT FALSE
}

CertEtcToken ::= CHOICE {
    certificate                  [0] IMPLICIT Certificate ,
    esscertid                    [1] ESSCertId ,
    pkistatus                    [2] IMPLICIT PKIStatusInfo ,
    assertion                    [3] ContentInfo ,
    crl                          [4] IMPLICIT CertificateList,
    ocspcertstatus               [5] IMPLICIT CertStatus,
    oscpcertid                   [6] IMPLICIT CertId ,
    oscpresponse                 [7] IMPLICIT OCSPResponse,
    capabilities                 [8] SMIMECapabilities,
    extension                    Extension
}

DVCSRequestInformation ::= SEQUENCE  {
       version                      INTEGER DEFAULT 1 ,
       service                      ServiceType,
       nonce                        Nonce OPTIONAL,
       requestTime                  DVCSTime OPTIONAL,
       requester                    [0] GeneralNames OPTIONAL,
       requestPolicy                [1] PolicyInformation OPTIONAL,
       dvcs                         [2] GeneralNames OPTIONAL,
       dataLocations                [3] GeneralNames OPTIONAL,
       extensions                   [4] IMPLICIT Extensions OPTIONAL
}

ServiceType ::= ENUMERATED { cpd(1), vsd(2), cpkc(3), ccpd(4) }



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DVCSRequest ::= SEQUENCE  {
   requestInformation         DVCSRequestInformation,
   data                       Data,
   transactionIdentifier      GeneralName OPTIONAL
}

Data ::= CHOICE {
     message           OCTET STRING ,
     messageImprint    DigestInfo,
     certs             SEQUENCE SIZE (1..MAX) OF
                           TargetEtcChain
}

DVCSResponse ::= CHOICE
{
   dvCertInfo         DVCSCertInfo ,
   dvErrorNote        [0] DVCSErrorNotice
}

DVCSCertInfo::= SEQUENCE  {
        version             Integer DEFAULT 1 ,
        dvReqInfo           DVCSRequestInformation,
        messageImprint      DigestInfo,
        serialNumber        Integer,
        responseTime        DVCSTime,
        dvStatus            [0] PKIStatusInfo OPTIONAL,
        policy              [1] PolicyInformation OPTIONAL,
        reqSignature        [2] SignerInfos  OPTIONAL,
        certs               [3] SEQUENCE SIZE (1..MAX) OF
                                TargetEtcChain OPTIONAL,
        extensions          Extensions OPTIONAL
}

DVCSErrorNotice ::= SEQUENCE {
   transactionStatus           PKIStatusInfo ,
   transactionIdentifier       GeneralName OPTIONAL
}

END

Appendix F - Examples

  This chapter contains an example of a request and a response of a
  'Certify Claim of Possession of Data' transaction of the Clepsydre
  Demonstration Project sponsored by La Poste, France.

  The information has been formatted with a slightly modified version
  of Peter Gutmann's dumpasn1 program.



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RFC 3029                     DVCS Protocols                February 2001


  The response Data Validation Certificate contains the signing
  certificate.

  The data that are time stamped is the binary of the client program
  used to make the request.

  Request:

  0 30  582: SEQUENCE {
  4 06    9:  OBJECT IDENTIFIER signedData (1 2 840 113549 1 7 2)
           : . (PKCS #7)
 15 A0  567:  [0] {
 19 30  563: . SEQUENCE {
 23 02    1: .  INTEGER 3
 26 31   11: .  SET {
 28 30    9: . . SEQUENCE {
 30 06    5: . .  OBJECT IDENTIFIER sha1 (1 3 14 3 2 26)
 37 05    0: . .  NULL
           : . .  }
           : . . }
 39 30  153: .  SEQUENCE {
 42 06   11: . . OBJECT IDENTIFIER
           : . .  id-ct-DVCSRequestData (1 2 840 113549 1 9 16 1 7)
           : . .  (S/MIME Content Types (1 2 840 113549 1 9 16 1))
 55 A0  137: . . [0] {
 58 04  134: . .  OCTET STRING, encapsulates {
 61 30  131: . . .  SEQUENCE {
 64 30   96: . . . . SEQUENCE {
 66 0A    1: . . . .  ENUMERATED CCPD (4)
 69 A0   77: . . . .  [0] {
 71 A4   75: . . . . . [4] {
 73 30   73: . . . . .  SEQUENCE {
 75 31   11: . . . . . . SET {
 77 30    9: . . . . . .  SEQUENCE {
 79 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  countryName (2 5 4 6)
           : . . . . . . .  (X.520 id-at (2 5 4))
 84 13    2: . . . . . . . PrintableString 'FR'
           : . . . . . . . }
           : . . . . . .  }
 88 31   14: . . . . . . SET {
 90 30   12: . . . . . .  SEQUENCE {
 92 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  localityName (2 5 4 7)
           : . . . . . . .  (X.520 id-at (2 5 4))
 97 13    5: . . . . . . . PrintableString 'Paris'
           : . . . . . . . }
           : . . . . . .  }



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RFC 3029                     DVCS Protocols                February 2001


104 31   16: . . . . . . SET {
106 30   14: . . . . . .  SEQUENCE {
108 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  organizationName (2 5 4 10)
           : . . . . . . .  (X.520 id-at (2 5 4))
113 13    7: . . . . . . . PrintableString 'EdelWeb'
           : . . . . . . . }
           : . . . . . .  }
122 31   24: . . . . . . SET {
124 30   22: . . . . . .  SEQUENCE {
126 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  commonName (2 5 4 3)
           : . . . . . . .  (X.520 id-at (2 5 4))
131 13   15: . . . . . . . PrintableString 'Peter Sylvester'
           : . . . . . . . }
           : . . . . . .  }
           : . . . . . . }
           : . . . . .  }
           : . . . . . }
148 A1   12: . . . .  [1] {
150 06   10: . . . . . OBJECT IDENTIFIER '1 3 6 1 4 1 5309 1 2 1'
           : . . . . . }
           : . . . .  }
162 30   31: . . . . SEQUENCE {
164 30    7: . . . .  SEQUENCE {
166 06    5: . . . . . OBJECT IDENTIFIER sha1 (1 3 14 3 2 26)
           : . . . . .  (OIW)
           : . . . . . }
173 04   20: . . . .  OCTET STRING
           : . . . .  75 B6 85 AF 6F 89 46 7D E8 07 15 25 1E 45 97 8F
           : . . . .  CD 1F A5 66
           : . . . .  }
           : . . . . }
           : . . .  }
           : . .  }
           : . . }
195 31  387: .  SET {
199 30  383: . . SEQUENCE {
203 02    1: . .  INTEGER 1
206 30  124: . .  SEQUENCE {
208 30  112: . . . SEQUENCE {
210 31   11: . . .  SET {
212 30    9: . . . . SEQUENCE {
214 06    3: . . . .  OBJECT IDENTIFIER countryName (2 5 4 6)
           : . . . . . (X.520 id-at (2 5 4))
219 13    2: . . . .  PrintableString 'FR'
           : . . . .  }
           : . . . . }



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RFC 3029                     DVCS Protocols                February 2001


223 31   21: . . .  SET {
225 30   19: . . . . SEQUENCE {
227 06    3: . . . .  OBJECT IDENTIFIER organizationName (2 5 4 10)
           : . . . . . (X.520 id-at (2 5 4))
232 13   12: . . . .  PrintableString 'EdelWeb S.A.'
           : . . . .  }
           : . . . . }
246 31   40: . . .  SET {
248 30   38: . . . . SEQUENCE {
250 06    3: . . . .  OBJECT IDENTIFIER
           : . . . . . organizationalUnitName (2 5 4 11)
           : . . . . . (X.520 id-at (2 5 4))
255 13 31: . . . .  PrintableString 'Clepsydre Demonstration Service'
           : . . . .  }
           : . . . . }
288 31   32: . . .  SET {
290 30   30: . . . . SEQUENCE {
292 06    3: . . . .  OBJECT IDENTIFIER commonName (2 5 4 3)
           : . . . . . (X.520 id-at (2 5 4))
297 13   23: . . . .  PrintableString 'Time Stamping Authority'
           : . . . .  }
           : . . . . }
           : . . .  }
322 02    8: . . . INTEGER
           : . . .  00 94 88 17 21 34 37 76
           : . . . }
332 30    9: . .  SEQUENCE {
334 06    5: . . . OBJECT IDENTIFIER sha1 (1 3 14 3 2 26)
           : . . .  (OIW)
341 05    0: . . . NULL
           : . . . }
343 A0   95: . .  [0] {
345 30   26: . . . SEQUENCE {
347 06    9: . . .  OBJECT IDENTIFIER
           : . . . . contentType (1 2 840 113549 1 9 3)
           : . . . . (PKCS #9 (1 2 840 113549 1 9))
358 31   13: . . .  SET {
360 06   11: . . . . OBJECT IDENTIFIER
           : . . . .  id-ct-dvcsrequest (1 2 840 113549 1 9 16 1 7)
           : . . . .  (S/MIME Content Types (1 2 840 113549 1 9 16 1))
           : . . . . }
           : . . .  }
373 30   28: . . . SEQUENCE {
375 06    9: . . .  OBJECT IDENTIFIER
           : . . . . signingTime (1 2 840 113549 1 9 5)
           : . . . . (PKCS #9 (1 2 840 113549 1 9))
386 31   15: . . .  SET {
388 17   13: . . . . UTCTime '000417171457Z'



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RFC 3029                     DVCS Protocols                February 2001


           : . . . . }
           : . . .  }
403 30   35: . . . SEQUENCE {
405 06    9: . . .  OBJECT IDENTIFIER
           : . . . . messageDigest (1 2 840 113549 1 9 4)
           : . . . . (PKCS #9 (1 2 840 113549 1 9))
416 31   22: . . .  SET {
418 04   20: . . . . OCTET STRING
           : . . . .  4D A8 C2 D2 CE 7C 0D 04 41 2F 44 13 33 75 DB 2F
           : . . . .  5B 2D F9 DC
           : . . . . }
           : . . .  }
           : . . . }
440 30   13: . .  SEQUENCE {
442 06    9: . . . OBJECT IDENTIFIER
           : . . .  rsaEncryption (1 2 840 113549 1 1 1)
           : . . .  (PKCS #1)
453 05    0: . . . NULL
           : . . . }
455 04  128: . .  OCTET STRING
           : . . . 6E 7B 0E 36 F5 08 5F 16 3C 31 7B 28 BB 0B C2 C6
           : . . . 17 67 A6 B5 54 F1 98 E2 6F 89 96 0E 0C 99 E6 CB
           : . . . 40 C1 9B 8D D8 D7 8E D3 2B 41 F7 16 26 5B B7 08
           : . . . BF E6 95 B2 D9 01 6C FE B1 2C 52 C1 5A D2 31 F3
           : . . . 8E CA DD 11 A1 72 05 29 41 6A DD 28 40 AA 5C 77
           : . . . C6 9D 1D 80 53 DB 6F 9C 4C A5 A3 8F 92 8B 18 3F
           : . . . D5 3A AD 01 87 69 C3 FD D3 D8 C3 D0 CA 6B E6 0D
           : . . . 4E 53 6E 50 20 99 7C 94 C2 44 25 1B 06 C0 99 96
           : . .  }
           : . . }
           : .  }
           : . }
           :  }

The corresponding data in PEM format are:

-----BEGIN PKCS7-----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Adams, et al.                 Experimental                     [Page 38]

RFC 3029                     DVCS Protocols                February 2001


BSlBat0oQKpcd8adHYBT22+cTKWjj5KLGD/VOq0Bh2nD/dPYw9DKa+YNTlNuUCCZ
fJTCRCUbBsCZlg==
-----END PKCS7-----

Response:

  0 30 2039: SEQUENCE {
  4 06    9:  OBJECT IDENTIFIER signedData (1 2 840 113549 1 7 2)
           : . (PKCS #7)
 15 A0 2024:  [0] {
 19 30 2020: . SEQUENCE {
 23 02    1: .  INTEGER 3
 26 31   11: .  SET {
 28 30    9: . . SEQUENCE {
 30 06    5: . .  OBJECT IDENTIFIER sha1 (1 3 14 3 2 26)
           : . . . (OIW)
 37 05    0: . .  NULL
           : . .  }
           : . . }
 39 30  301: .  SEQUENCE {
 43 06   11: . . OBJECT IDENTIFIER
           : . .  id-ct-DVCSResponseData (1 2 840 113549 1 9 16 1 8)
           : . .  (S/MIME Content Types (1 2 840 113549 1 9 16 1))
 56 A0  284: . . [0] {
 60 04  280: . .  OCTET STRING, encapsulates {
 64 30  276: . . .  SEQUENCE {
 68 30  214: . . . . SEQUENCE {
 71 0A    1: . . . .  ENUMERATED CCPD (4)
 74 A0   77: . . . .  [0] {
 76 A4   75: . . . . . [4] {
 78 30   73: . . . . .  SEQUENCE {
 80 31   11: . . . . . . SET {
 82 30    9: . . . . . .  SEQUENCE {
 84 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  countryName (2 5 4 6)
           : . . . . . . .  (X.520 id-at (2 5 4))
 89 13    2: . . . . . . . PrintableString 'FR'
           : . . . . . . . }
           : . . . . . .  }
 93 31   14: . . . . . . SET {
 95 30   12: . . . . . .  SEQUENCE {
 97 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  localityName (2 5 4 7)
           : . . . . . . .  (X.520 id-at (2 5 4))
102 13    5: . . . . . . . PrintableString 'Paris'
           : . . . . . . . }
           : . . . . . .  }
109 31   16: . . . . . . SET {



Adams, et al.                 Experimental                     [Page 39]

RFC 3029                     DVCS Protocols                February 2001


111 30   14: . . . . . .  SEQUENCE {
113 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  organizationName (2 5 4 10)
           : . . . . . . .  (X.520 id-at (2 5 4))
118 13    7: . . . . . . . PrintableString 'EdelWeb'
           : . . . . . . . }
           : . . . . . .  }
127 31   24: . . . . . . SET {
129 30   22: . . . . . .  SEQUENCE {
131 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  commonName (2 5 4 3)
           : . . . . . . .  (X.520 id-at (2 5 4))
136 13   15: . . . . . . . PrintableString 'Peter Sylvester'
           : . . . . . . . }
           : . . . . . .  }
           : . . . . . . }
           : . . . . .  }
           : . . . . . }
153 A1   12: . . . .  [1] {
155 06   10: . . . . . OBJECT IDENTIFIER '1 3 6 1 4 1 5309 1 2 1'
           : . . . . . }
167 A2  116: . . . .  [2] {
169 A4  114: . . . . . [4] {
171 30  112: . . . . .  SEQUENCE {
173 31   11: . . . . . . SET {
175 30    9: . . . . . .  SEQUENCE {
177 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  countryName (2 5 4 6)
           : . . . . . . .  (X.520 id-at (2 5 4))
182 13    2: . . . . . . . PrintableString 'FR'
           : . . . . . . . }
           : . . . . . .  }
186 31   21: . . . . . . SET {
188 30   19: . . . . . .  SEQUENCE {
190 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  organizationName (2 5 4 10)
           : . . . . . . .  (X.520 id-at (2 5 4))
195 13   12: . . . . . . . PrintableString 'EdelWeb S.A.'
           : . . . . . . . }
           : . . . . . .  }
209 31   40: . . . . . . SET {
211 30   38: . . . . . .  SEQUENCE {
213 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  organizationalUnitName (2 5 4 11)
           : . . . . . . .  (X.520 id-at (2 5 4))
218 13 31: . . . . . PrintableString 'Clepsydre Demonstration Service'
           : . . . . . . . }
           : . . . . . .  }



Adams, et al.                 Experimental                     [Page 40]

RFC 3029                     DVCS Protocols                February 2001


251 31   32: . . . . . . SET {
253 30   30: . . . . . .  SEQUENCE {
255 06    3: . . . . . . . OBJECT IDENTIFIER
           : . . . . . . .  commonName (2 5 4 3)
           : . . . . . . .  (X.520 id-at (2 5 4))
260 13   23: . . . . . . . PrintableString 'Time Stamping Authority'
           : . . . . . . . }
           : . . . . . .  }
           : . . . . . . }
           : . . . . .  }
           : . . . . . }
           : . . . .  }
285 30   31: . . . . SEQUENCE {
287 30    7: . . . .  SEQUENCE {
289 06    5: . . . . . OBJECT IDENTIFIER sha1 (1 3 14 3 2 26)
           : . . . . . }
296 04   20: . . . .  OCTET STRING
           : . . . .  75 B6 85 AF 6F 89 46 7D E8 07 15 25 1E 45 97 8F
           : . . . .  CD 1F A5 66
           : . . . .  }
318 02    7: . . . . INTEGER
           : . . . .  01 78 0A 1E CA 88 23
327 18   15: . . . . GeneralizedTime '20000417171617Z'
           : . . . . }
           : . . .  }
           : . .  }
           : . . }
344 A0  992: .  [0] {
348 30  988: . . SEQUENCE {
352 30  708: . .  SEQUENCE {
356 A0    3: . . . [0] {
358 02    1: . . .  INTEGER 2
           : . . .  }
361 02    8: . . . INTEGER
           : . . .  00 94 88 17 17 64 37 32
371 30   13: . . . SEQUENCE {
373 06    9: . . .  OBJECT IDENTIFIER
           : . . . . md5withRSAEncryption (1 2 840 113549 1 1 4)
           : . . . . (PKCS #1)
384 05    0: . . .  NULL
           : . . .  }
386 30  112: . . . SEQUENCE {
388 31   11: . . .  SET {
390 30    9: . . . . SEQUENCE {
392 06    3: . . . .  OBJECT IDENTIFIER countryName (2 5 4 6)
           : . . . . . (X.520 id-at (2 5 4))
397 13    2: . . . .  PrintableString 'FR'
           : . . . .  }



Adams, et al.                 Experimental                     [Page 41]

RFC 3029                     DVCS Protocols                February 2001


           : . . . . }
401 31   21: . . .  SET {
403 30   19: . . . . SEQUENCE {
405 06    3: . . . .  OBJECT IDENTIFIER organizationName (2 5 4 10)
           : . . . . . (X.520 id-at (2 5 4))
410 13   12: . . . .  PrintableString 'EdelWeb S.A.'
           : . . . .  }
           : . . . . }
424 31   40: . . .  SET {
426 30   38: . . . . SEQUENCE {
428 06    3: . . . .  OBJECT IDENTIFIER
           : . . . . . organizationalUnitName (2 5 4 11)
           : . . . . . (X.520 id-at (2 5 4))
433 13 31: . . . .  PrintableString 'Clepsydre Demonstration Service'
           : . . . .  }
           : . . . . }
466 31   32: . . .  SET {
468 30   30: . . . . SEQUENCE {
470 06    3: . . . .  OBJECT IDENTIFIER commonName (2 5 4 3)
           : . . . . . (X.520 id-at (2 5 4))
475 13   23: . . . .  PrintableString 'Time Stamping Authority'
           : . . . .  }
           : . . . . }
           : . . .  }
500 30   30: . . . SEQUENCE {
502 17   13: . . .  UTCTime '000125161938Z'
517 17   13: . . .  UTCTime '200120161938Z'
           : . . .  }
532 30  112: . . . SEQUENCE {
534 31   11: . . .  SET {
536 30    9: . . . . SEQUENCE {
538 06    3: . . . .  OBJECT IDENTIFIER countryName (2 5 4 6)
           : . . . . . (X.520 id-at (2 5 4))
543 13    2: . . . .  PrintableString 'FR'
           : . . . .  }
           : . . . . }
547 31   21: . . .  SET {
549 30   19: . . . . SEQUENCE {
551 06    3: . . . .  OBJECT IDENTIFIER organizationName (2 5 4 10)
           : . . . . . (X.520 id-at (2 5 4))
556 13   12: . . . .  PrintableString 'EdelWeb S.A.'
           : . . . .  }
           : . . . . }
570 31   40: . . .  SET {
572 30   38: . . . . SEQUENCE {
574 06    3: . . . .  OBJECT IDENTIFIER
           : . . . . . organizationalUnitName (2 5 4 11)
           : . . . . . (X.520 id-at (2 5 4))



Adams, et al.                 Experimental                     [Page 42]

RFC 3029                     DVCS Protocols                February 2001


579 13 31: . . . .  PrintableString 'Clepsydre Demonstration Service'
           : . . . .  }
           : . . . . }
612 31   32: . . .  SET {
614 30   30: . . . . SEQUENCE {
616 06    3: . . . .  OBJECT IDENTIFIER commonName (2 5 4 3)
           : . . . . . (X.520 id-at (2 5 4))
621 13   23: . . . .  PrintableString 'Time Stamping Authority'
           : . . . .  }
           : . . . . }
           : . . .  }
646 30  290: . . . SEQUENCE {
650 30   13: . . .  SEQUENCE {
652 06    9: . . . . OBJECT IDENTIFIER
           : . . . .  rsaEncryption (1 2 840 113549 1 1 1)
           : . . . .  (PKCS #1)
663 05    0: . . . . NULL
           : . . . . }
665 03  271: . . .  BIT STRING 0 unused bits
           : . . . . 30 82 01 0A 02 82 01 01 00 FA C3 17 AE EB B7 9D
           : . . . . EB AB BD 05 7E 39 43 6D 04 45 58 74 05 A5 CC F3
           : . . . . 6C 2F 8C 8E 77 7E C2 9F 12 11 5C 7D DB BE 23 28
           : . . . . 9A 90 D2 AB C6 A2 BA BD A3 7E 99 A6 99 21 A5 D8
           : . . . . 90 B9 CF A7 23 4E A0 56 A0 C1 0A 46 89 8E 3C 91
           : . . . . 67 37 FD 9B AB 49 17 FC 4A A5 F2 E4 4C 6E E3 6A
           : . . . . 1C 92 97 04 6F 7F 0C 5C FB 74 CB 95 7E 4C C3 58
           : . . . . 12 E8 A9 D6 F0 DD 12 44 15 E7 8B 2E AF 51 C0 0C
           : . . . . . . [ Another 142 bytes skipped ]
           : . . .  }
940 A3  122: . . . [3] {
942 30  120: . . .  SEQUENCE {
944 30   15: . . . . SEQUENCE {
946 06    3: . . . .  OBJECT IDENTIFIER basicConstraints (2 5 29 19)
           : . . . . . (X.509 id-ce (2 5 29))
951 04    8: . . . .  OCTET STRING, encapsulates {
953 30    6: . . . . .  SEQUENCE {
955 01    1: . . . . . . BOOLEAN TRUE
958 02    1: . . . . . . INTEGER 0
           : . . . . . . }
           : . . . . .  }
           : . . . .  }
961 30   22: . . . . SEQUENCE {
963 06    3: . . . .  OBJECT IDENTIFIER extKeyUsage (2 5 29 37)
           : . . . . . (X.509 id-ce (2 5 29))
968 01    1: . . . .  BOOLEAN TRUE
971 04   12: . . . .  OCTET STRING, encapsulates {
973 30   10: . . . . .  SEQUENCE {
975 06    8: . . . . . . OBJECT IDENTIFIER '1 3 6 1 5 5 7 3 10'



Adams, et al.                 Experimental                     [Page 43]

RFC 3029                     DVCS Protocols                February 2001


           : . . . . . . }
           : . . . . .  }
           : . . . .  }
985 30   77: . . . . SEQUENCE {
987 06    8: . . . .  OBJECT IDENTIFIER
           : . . . . . authorityInfoAccess (1 3 6 1 5 5 7 1 1)
           : . . . . . (PKIX private extension)
997 01    1: . . . .  BOOLEAN TRUE
1000 04   62: . . . .  OCTET STRING, encapsulates {
1002 30   60: . . . . .  SEQUENCE {
1004 30   58: . . . . . . SEQUENCE {
1006 06    8: . . . . . .  OBJECT IDENTIFIER '1 3 6 1 5 5 7 48 4'
1016 86   46: . . . . . .  [6]
           : . . . .  'https://clepsydre.edelweb.fr/dvcs/service-ccpd'
           : . . . . . .  }
           : . . . . . . }
           : . . . . .  }
           : . . . .  }
           : . . . . }
           : . . .  }
           : . . . }
1064 30   13: . .  SEQUENCE {
1066 06    9: . . . OBJECT IDENTIFIER
           : . . .  md5withRSAEncryption (1 2 840 113549 1 1 4)
           : . . .  (PKCS #1)
1077 05    0: . . . NULL
           : . . . }
1079 03  257: . .  BIT STRING 0 unused bits
           : . . . 08 DA AF 5B 09 39 66 D3 BE 80 1D D7 72 B5 2C A3
           : . . . 04 FB 46 F8 05 F5 BF 83 F3 6D 6D 32 28 1C 46 EE
           : . . . 0F EA 30 61 8A 1E 8A 03 4E 98 81 60 1F 97 17 53
           : . . . D1 54 73 3F 72 98 45 D3 10 9A D3 77 B8 74 0E 9A
           : . . . 90 29 8E AC A4 EB D2 24 6D F6 21 1D 3F 52 8B 2C
           : . . . E6 92 E7 52 C6 54 93 91 BC 57 74 21 38 39 75 CD
           : . . . 30 49 54 13 94 6C FE F1 64 38 1F 5F 7D BB E0 3E
           : . . . A8 F1 28 1C F1 D9 28 FA 32 1E 3B 48 BF 5C 70 21
           : . . . . . [ Another 128 bytes skipped ]
           : . .  }
           : . . }
1340 31  699: .  SET {
1344 30  695: . . SEQUENCE {
1348 02    1: . .  INTEGER 1
1351 30  124: . .  SEQUENCE {
1353 30  112: . . . SEQUENCE {
1355 31   11: . . .  SET {
1357 30    9: . . . . SEQUENCE {
1359 06    3: . . . .  OBJECT IDENTIFIER countryName (2 5 4 6)
           : . . . . . (X.520 id-at (2 5 4))



Adams, et al.                 Experimental                     [Page 44]

RFC 3029                     DVCS Protocols                February 2001


1364 13    2: . . . .  PrintableString 'FR'
           : . . . .  }
           : . . . . }
1368 31   21: . . .  SET {
1370 30   19: . . . . SEQUENCE {
1372 06    3: . . . .  OBJECT IDENTIFIER organizationName (2 5 4 10)
           : . . . . . (X.520 id-at (2 5 4))
1377 13   12: . . . .  PrintableString 'EdelWeb S.A.'
           : . . . .  }
           : . . . . }
1391 31   40: . . .  SET {
1393 30   38: . . . . SEQUENCE {
1395 06    3: . . . .  OBJECT IDENTIFIER
           : . . . . . organizationalUnitName (2 5 4 11)
           : . . . . . (X.520 id-at (2 5 4))
1400 13 31: . . . .  PrintableString 'Clepsydre Demonstration Service'
           : . . . .  }
           : . . . . }
1433 31   32: . . .  SET {
1435 30   30: . . . . SEQUENCE {
1437 06    3: . . . .  OBJECT IDENTIFIER commonName (2 5 4 3)
           : . . . . . (X.520 id-at (2 5 4))
1442 13   23: . . . .  PrintableString 'Time Stamping Authority'
           : . . . .  }
           : . . . . }
           : . . .  }
1467 02    8: . . . INTEGER
           : . . .  00 94 88 25 72 35 27 50
           : . . . }
1477 30    9: . .  SEQUENCE {
1479 06    5: . . . OBJECT IDENTIFIER sha1 (1 3 14 3 2 26)
           : . . .  (OIW)
1486 05    0: . . . NULL
           : . . . }
1488 A0  276: . .  [0] {
1492 30   26: . . . SEQUENCE {
1494 06    9: . . .  OBJECT IDENTIFIER
           : . . . . contentType (1 2 840 113549 1 9 3)
           : . . . . (PKCS #9 (1 2 840 113549 1 9))
1505 31   13: . . .  SET {
1507 06   11: . . . . OBJECT IDENTIFIER
           : . . . .  id-ct-dvcsresponse (1 2 840 113549 1 9 16 1 8)
           : . . . .  (S/MIME Content Types (1 2 840 113549 1 9 16 1))
           : . . . . }
           : . . .  }
1520 30   28: . . . SEQUENCE {
1522 06    9: . . .  OBJECT IDENTIFIER
           : . . . . signingTime (1 2 840 113549 1 9 5)



Adams, et al.                 Experimental                     [Page 45]

RFC 3029                     DVCS Protocols                February 2001


           : . . . . (PKCS #9 (1 2 840 113549 1 9))
1533 31   15: . . .  SET {
1535 17   13: . . . . UTCTime '000417171619Z'
           : . . . . }
           : . . .  }
1550 30   35: . . . SEQUENCE {
1552 06    9: . . .  OBJECT IDENTIFIER
           : . . . . messageDigest (1 2 840 113549 1 9 4)
           : . . . . (PKCS #9 (1 2 840 113549 1 9))
1563 31   22: . . .  SET {
1565 04   20: . . . . OCTET STRING
           : . . . .  68 50 DC 90 20 2E C2 F0 55 15 7F 77 A9 A6 0C 34
           : . . . .  CC 13 06 FA
           : . . . . }
           : . . .  }
1587 30  178: . . . SEQUENCE {
1590 06   11: . . .  OBJECT IDENTIFIER
         : . . . id-aa-signingCertificate (1 2 840 113549 1 9 16 2 12)
     : . . (S/MIME Authenticated Attributes (1 2 840 113549 1 9 16 2))
1603 31  162: . . .  SET {
1606 30  159: . . . . SEQUENCE {
1609 30  156: . . . .  SEQUENCE {
1612 30  153: . . . . . SEQUENCE {
1615 04   20: . . . . .  OCTET STRING
           : . . . .  5C F1 18 F3 4A CA B4 67 D6 D8 E7 F8 3B 4A D9 7A
           : . . . .  32 A5 43 A5
1637 30  128: . . . . .  SEQUENCE {
1640 30  116: . . . . . . SEQUENCE {
1642 A4  114: . . . . . .  [4] {
1644 30  112: . . . . . . . SEQUENCE {
1646 31   11: . . . . . . .  SET {
1648 30    9: . . . . . . . . SEQUENCE {
1650 06    3: . . . . . . . .  OBJECT IDENTIFIER
           : . . . . . . . . . countryName (2 5 4 6)
           : . . . . . . . . . (X.520 id-at (2 5 4))
1655 13    2: . . . . . . . .  PrintableString 'FR'
           : . . . . . . . .  }
           : . . . . . . . . }
1659 31   21: . . . . . . .  SET {
1661 30   19: . . . . . . . . SEQUENCE {
1663 06    3: . . . . . . . .  OBJECT IDENTIFIER
           : . . . . . . . . . organizationName (2 5 4 10)
           : . . . . . . . . . (X.520 id-at (2 5 4))
1668 13   12: . . . . . . . .  PrintableString 'EdelWeb S.A.'
           : . . . . . . . .  }
           : . . . . . . . . }
1682 31   40: . . . . . . .  SET {
1684 30   38: . . . . . . . . SEQUENCE {



Adams, et al.                 Experimental                     [Page 46]

RFC 3029                     DVCS Protocols                February 2001


1686 06    3: . . . . . . . .  OBJECT IDENTIFIER
           : . . . . . . . . . organizationalUnitName (2 5 4 11)
           : . . . . . . . . . (X.520 id-at (2 5 4))
1691 13 31: . . . . .PrintableString 'Clepsydre Demonstration Service'
           : . . . . . . . .  }
           : . . . . . . . . }
1724 31   32: . . . . . . .  SET {
1726 30   30: . . . . . . . . SEQUENCE {
1728 06    3: . . . . . . . .  OBJECT IDENTIFIER
           : . . . . . . . . . commonName (2 5 4 3)
           : . . . . . . . . . (X.520 id-at (2 5 4))
1733 13 23: . . . . . . . .  PrintableString 'Time Stamping Authority'
           : . . . . . . . .  }
           : . . . . . . . . }
           : . . . . . . .  }
           : . . . . . . . }
           : . . . . . .  }
1758 02    8: . . . . . . INTEGER
           : . . . .  00 94 88 25 72 35 27 50
           : . . . . . . }
           : . . . . .  }
           : . . . . . }
           : . . . .  }
           : . . . . }
           : . . .  }
           : . . . }
1768 30   13: . .  SEQUENCE {
1770 06    9: . . . OBJECT IDENTIFIER
           : . . .  rsaEncryption (1 2 840 113549 1 1 1)
           : . . .  (PKCS #1)
1781 05    0: . . . NULL
           : . . . }
1783 04  256: . .  OCTET STRING
           : . . . 2E 70 9F 56 5E 01 56 A9 E1 47 81 12 35 21 29 09
           : . . . 16 7A ED 45 F9 5A A2 ED E4 FE 9D 2C E4 DA 12 66
           : . . . 62 14 59 61 8B 50 7B 01 82 3D BD 7E E6 38 D0 A8
           : . . . A0 37 98 79 13 26 39 29 C6 72 20 A9 95 71 E7 53
           : . . . 7F 79 77 98 EF 23 02 4E B9 BD 90 9B AC 05 A2 70
           : . . . 8F 3A 42 36 9C 2C B0 94 B1 2B 0B 36 94 0E 78 0E
           : . . . B0 D1 09 20 63 BC FF CD 32 F1 5A D3 AB 9F 93 9C
           : . . . 5A A3 58 99 A0 28 11 E0 80 4D 4D 1E 77 04 F4 50
           : . . . . . [ Another 128 bytes skipped ]
           : . .  }
           : . . }
           : .  }
           : . }
           :  }




Adams, et al.                 Experimental                     [Page 47]

RFC 3029                     DVCS Protocols                February 2001


The corresponding data in PEM format (together with a technical textual
description) are:

Data Validation Certificate:
   Request Information:
     Service: Certify Claim of Possession of Data - ccpd(4)
     Policy: EdelWeb Customer Policy Clepsydre
     Requester:
       DirName:/C=FR/L=Paris/O=EdelWeb/CN=Peter Sylvester
     DVCS:
       DirName:/C=FR/O=EdelWeb S.A./
 OU=Clepsydre Demonstration Service/CN=Time Stamping Authority
   SerialNumber: 01780a1eca8823
   MessageDigest:
     Algorithm: sha1
     Data     : 75B685AF6F89467DE80715251E45978FCD1FA566
   Asserted Time:
     Generalized Time: 17-Apr-2000 19:16:17 (Apr 17 17:16:17 2000 GMT)
Certificate:
   Data:
       Version: 3 (0x2)
       Serial Number:
           94:88:17:17:64:37:32
       Signature Algorithm: md5WithRSAEncryption
       Issuer: C=FR, O=EdelWeb S.A.,
   OU=Clepsydre Demonstration Service, CN=Time Stamping Authority
       Validity
           Not Before: Jan 25 16:19:38 2000 GMT
           Not After : Jan 20 16:19:38 2020 GMT
       Subject: C=FR, O=EdelWeb S.A.,
   OU=Clepsydre Demonstration Service, CN=Time Stamping Authority
       Subject Public Key Info:
           Public Key Algorithm: rsaEncryption
           RSA Public Key: (2048 bit)
               Modulus (2048 bit):
                   00:fa:c3:17:ae:eb:b7:9d:eb:ab:bd:05:7e:39:43:
                   6d:04:45:58:74:05:a5:cc:f3:6c:2f:8c:8e:77:7e:
                   c2:9f:12:11:5c:7d:db:be:23:28:9a:90:d2:ab:c6:
                   a2:ba:bd:a3:7e:99:a6:99:21:a5:d8:90:b9:cf:a7:
                   23:4e:a0:56:a0:c1:0a:46:89:8e:3c:91:67:37:fd:
                   9b:ab:49:17:fc:4a:a5:f2:e4:4c:6e:e3:6a:1c:92:
                   97:04:6f:7f:0c:5c:fb:74:cb:95:7e:4c:c3:58:12:
                   e8:a9:d6:f0:dd:12:44:15:e7:8b:2e:af:51:c0:0c:
                   5f:a8:65:fc:47:a1:c9:98:1f:d4:e1:ea:bc:1c:1a:
                   27:bb:8b:56:f1:12:55:10:f4:8e:d8:9f:19:9c:1e:
                   81:f7:db:63:dd:88:37:3f:71:79:5b:96:e2:5f:82:
                   d5:12:19:05:0d:e1:3d:a5:6d:66:e4:2c:1e:ed:c7:
                   4c:b8:df:aa:38:c8:15:6a:ae:25:7d:46:2a:07:f9:



Adams, et al.                 Experimental                     [Page 48]

RFC 3029                     DVCS Protocols                February 2001


                   83:77:c4:51:ee:90:dc:05:d0:c3:f0:f1:5f:e8:d4:
                   ed:5d:34:70:91:9d:9f:08:55:7d:5b:e5:8d:5f:35:
                   59:83:4e:72:19:bb:9c:88:d1:7a:fc:23:a5:84:99:
                   b4:17:8a:4d:6c:9d:d0:a6:35:80:5f:ca:fb:24:8b:
                   54:1d
               Exponent: 65537 (0x10001)
       X509v3 extensions:
           X509v3 Basic Constraints:
               CA:TRUE, pathlen:0
           X509v3 Extended Key Usage: critical
               DVCS Signing
           Authority Information Access: critical
        DVCS - URI:https://clepsydre.edelweb.fr/dvcs/service-ccpd

   Signature Algorithm: md5WithRSAEncryption
       08:da:af:5b:09:39:66:d3:be:80:1d:d7:72:b5:2c:a3:04:fb:
       46:f8:05:f5:bf:83:f3:6d:6d:32:28:1c:46:ee:0f:ea:30:61:
       8a:1e:8a:03:4e:98:81:60:1f:97:17:53:d1:54:73:3f:72:98:
       45:d3:10:9a:d3:77:b8:74:0e:9a:90:29:8e:ac:a4:eb:d2:24:
       6d:f6:21:1d:3f:52:8b:2c:e6:92:e7:52:c6:54:93:91:bc:57:
       74:21:38:39:75:cd:30:49:54:13:94:6c:fe:f1:64:38:1f:5f:
       7d:bb:e0:3e:a8:f1:28:1c:f1:d9:28:fa:32:1e:3b:48:bf:5c:
       70:21:29:ef:be:72:24:da:0d:f9:51:7a:fe:d7:f5:ff:e8:c2:
       ea:c6:4c:45:14:51:53:fd:00:d5:5b:cc:67:2a:23:94:31:9e:
       c2:90:38:9b:b0:df:f9:de:67:0c:57:5c:d7:b0:fc:f2:72:96:
       c4:d1:7a:9d:a0:e6:51:24:99:9e:89:c6:39:f9:72:7a:44:fd:
       2d:3f:bc:df:c7:25:27:94:a1:b5:7d:ba:06:75:67:1c:95:6c:
       bd:2c:74:41:3e:cd:cd:39:5c:2e:9c:c3:c3:09:e3:79:d5:eb:
       85:e8:f1:72:29:80:f6:c6:6e:61:1b:58:fc:87:3e:d9:e1:53:
       10:e0:b1:05

-----BEGIN PKCS7-----
MIIH9wYJKoZIhvcNAQcCoIIH6DCCB+QCAQMxCzAJBgUrDgMCGgUAMIIBLQYLKoZI
hvcNAQkQAQigggEcBIIBGDCCARQwgdYKAQSgTaRLMEkxCzAJBgNVBAYTAkZSMQ4w
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0qvGorq9o36ZppkhpdiQuc+nI06gVqDBCkaJjjyRZzf9m6tJF/xKpfLkTG7jahyS



Adams, et al.                 Experimental                     [Page 49]

RFC 3029                     DVCS Protocols                February 2001


lwRvfwxc+3TLlX5Mw1gS6KnW8N0SRBXniy6vUcAMX6hl/EehyZgf1OHqvBwaJ7uL
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QS4xKDAmBgNVBAsTH0NsZXBzeWRyZSBEZW1vbnN0cmF0aW9uIFNlcnZpY2UxIDAe
BgNVBAMTF1RpbWUgU3RhbXBpbmcgQXV0aG9yaXR5AggAlIglcjUnUDANBgkqhkiG
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LLCUsSsLNpQOeA6w0QkgY7z/zTLxWtOrn5OcWqNYmaAoEeCATU0edwT0UAfVi1Sg
IzL/ppziurjbVUfJyLoH75AUSKi2xXzVqSB0HFbvjxuz/IdtgfHUbxqHMJJHaeB5
4LwQmc9NNkw2A1Fy0VumHi2G8R8K6L/rOPnOGuywj1GuKjtGhL9NjJ/uH+/FNaNj
vjjAA3w6XrjPOxgQiNu7T3j2++QcjdT4++tQ
-----END PKCS7-----

Appendix G - Acknowledgements

  This document is based on two initial works from Robert Zuccherato
  and Carlisle Adams, both at Entrust Technologies, for time stamping
  and for notary and data certification services.

  Thanks to Denis Pinkas, Bull and Bruno Salgueiro, SIBS for valuable
  comments.














Adams, et al.                 Experimental                     [Page 50]

RFC 3029                     DVCS Protocols                February 2001


Full Copyright Statement

  Copyright (C) The Internet Society (2001).  All Rights Reserved.

  This document and translations of it may be copied and furnished to
  others, and derivative works that comment on or otherwise explain it
  or assist in its implementation may be prepared, copied, published
  and distributed, in whole or in part, without restriction of any
  kind, provided that the above copyright notice and this paragraph are
  included on all such copies and derivative works.  However, this
  document itself may not be modified in any way, such as by removing
  the copyright notice or references to the Internet Society or other
  Internet organizations, except as needed for the purpose of
  developing Internet standards in which case the procedures for
  copyrights defined in the Internet Standards process must be
  followed, or as required to translate it into languages other than
  English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.

  This document and the information contained herein is provided on an
  "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
  TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
  BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
  HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
  MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.



















Adams, et al.                 Experimental                     [Page 51]