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Versions: 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 RFC 6712

Network Working Group                                          A. Kapoor
Internet-Draft                                              R. Tschalaer
Updates: 2510,4210                                              Certicom
(if approved)                                                   T. Kause
Intended status: Standards Track                                     SSH
Expires: January 31, 2010                                       M. Peylo
                                                                     NSN
                                                           July 30, 2009


Internet X.509 Public Key Infrastructure -- Transport Protocols for CMP
             draft-ietf-pkix-cmp-transport-protocols-06.txt

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
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   This Internet-Draft will expire on January 31, 2010.

Copyright Notice




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   Copyright (c) 2009 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents in effect on the date of
   publication of this document (http://trustee.ietf.org/license-info).
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.











































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Abstract

   This document describes how to layer Certificate Management Protocols
   over various transport protocols.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
   2.  Requirements . . . . . . . . . . . . . . . . . . . . . . . . .  5
   3.  TCP-Based Management Protocol  . . . . . . . . . . . . . . . .  6
     3.1.  General Form . . . . . . . . . . . . . . . . . . . . . . .  6
     3.2.  Version  . . . . . . . . . . . . . . . . . . . . . . . . .  7
       3.2.1.  Version Negotiation  . . . . . . . . . . . . . . . . .  7
       3.2.2.  Detection and Interoperation with RFC2510
               Conformant Implementations . . . . . . . . . . . . . .  8
     3.3.  Flags  . . . . . . . . . . . . . . . . . . . . . . . . . .  8
       3.3.1.  Connection Close Flag  . . . . . . . . . . . . . . . .  8
     3.4.  Message-Types  . . . . . . . . . . . . . . . . . . . . . .  9
       3.4.1.  pkiReq . . . . . . . . . . . . . . . . . . . . . . . .  9
       3.4.2.  pkiRep . . . . . . . . . . . . . . . . . . . . . . . . 10
       3.4.3.  pollReq  . . . . . . . . . . . . . . . . . . . . . . . 10
       3.4.4.  pollRep  . . . . . . . . . . . . . . . . . . . . . . . 10
       3.4.5.  finRep . . . . . . . . . . . . . . . . . . . . . . . . 11
       3.4.6.  errorMsgRep  . . . . . . . . . . . . . . . . . . . . . 11
         3.4.6.1.  VersionNotSupported  . . . . . . . . . . . . . . . 12
         3.4.6.2.  GeneralClientError . . . . . . . . . . . . . . . . 13
         3.4.6.3.  InvalidMessageType . . . . . . . . . . . . . . . . 13
         3.4.6.4.  InvalidPollID  . . . . . . . . . . . . . . . . . . 14
         3.4.6.5.  GeneralServerError . . . . . . . . . . . . . . . . 14
   4.  HTTP-Based Protocol  . . . . . . . . . . . . . . . . . . . . . 15
     4.1.  HTTP Versions  . . . . . . . . . . . . . . . . . . . . . . 15
     4.2.  General Form . . . . . . . . . . . . . . . . . . . . . . . 15
     4.3.  MIME Type  . . . . . . . . . . . . . . . . . . . . . . . . 15
     4.4.  HTTP Considerations  . . . . . . . . . . . . . . . . . . . 15
     4.5.  Compatibility Issues with Legacy Implementations . . . . . 15
   5.  File-Based Protocol  . . . . . . . . . . . . . . . . . . . . . 17
   6.  Mail-Based Protocol  . . . . . . . . . . . . . . . . . . . . . 18
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 19
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 20
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 20
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 20
   Appendix A.  Acknowledgments . . . . . . . . . . . . . . . . . . . 21
   Appendix B.  Registration of the application/pkixcmp Media Type  . 22
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 24






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1.  Introduction

   Well defined transport mechanisms are required for the Certificate
   Management Protocol [RFC4210] in order to allow end entities, RAs and
   CAs to pass PKIMessage sequences between them.














































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2.  Requirements

   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].














































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3.  TCP-Based Management Protocol

   While this section is called TCP-based and the messages are called
   TCP-Messages, the same protocol can be used over any reliable,
   connection oriented transport protocol (e.g.  SNA, DECnet, etc.).
   This protocol is suitable for cases where an end entity (or an RA)
   initiates a transaction and can poll to pick up the results.

   The client sends a TCP-Message to the server, and the server responds
   with another TCP-Message.  A response MUST be sent for every request,
   even if the encapsulated CMP message in the request does not have a
   corresponding response.

   The protocol requires a listener process on an RA or CA which can
   accept TCP-Messages on a well-defined port (default TCP port number
   is 829).  Typically a client initiates the connection to the server
   and instantly submits a TCP-Message.  The server replies with a TCP-
   Message containing either a CMP message or a reference number to be
   used later when polling for the actual CMP response message.

   If a polling-reference was supplied, the client SHOULD send a polling
   request using this polling-reference after waiting for at least the
   time specified along with the reference number.  The server may again
   reply with a new polling-reference or with the actual CMP message
   response.

   When the final CMP response message has been picked up by the client,
   no new polling reference is supplied.

3.1.  General Form

   The format of a TCP-Message is shown below:

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                            Length                             |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Version = 10 |     Flags     |  Message-Type |               \
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+               /
     \                                                               \
     /                     Value (variable length)                   /
     \                                                               \
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+







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   Length: 32 bits (unsigned integer)
       This field contains the number of remaining octets of the TCP-
       Message (i.e. number of octets of the Value field plus 3).  All
       bit values in this protocol are specified to be in network byte
       order.

   Version: 8-bits (unsigned integer)
       The version of the TCP-Message is 10 in for this document.  It
       MUST be incremented in each future specification modification
       e.g. changing the Flags field in a way that is not fully
       backwards compatible.

   Flags: 8 bits
       TCP-Message specific flags as described in Section 3.3.

   Message-Type: 8 bits
       A value indicating the type of the TCP-Message.

   Value: variable length
       Message-type dependent data is stored here.  The usage of this
       field is described along with the respective message-type

3.2.  Version

   The TCP-Message version is 10 for this document.  The number has
   deliberately been chosen to prevent [RFC2510] compliant applications
   from treating it as a valid message type.  Applications receiving a
   version less than 10 SHOULD interpret the message as being an
   [RFC2510] style message.

3.2.1.  Version Negotiation

   If a client knows the protocol version(s) supported by the server
   (e.g. from a previous TCP-Message exchange or via some out-of-band
   means) then it SHOULD send a TCP-Message with the highest version
   supported both by it and the server.  If a client does not know what
   version(s) the server supports then it SHOULD send a TCP-Message
   using the highest version it supports.

   If a server receives a TCP-Message version that it supports, then it
   MUST reply with a TCP-Message of the same version.  If the version
   received is higher than what the server supports, it MUST send back a
   VersionNotSupported errorMsgRep containing the highest version it
   supports, see Section 3.4.6.







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3.2.2.  Detection and Interoperation with RFC2510 Conformant
        Implementations

   Servers wishing to interoperate with clients conforming to [RFC2510]
   can do so by treating any received message with a version less than
   10 as an [RFC2510] message and responding in that format.  Servers
   not wishing to support [RFC2510] messages MUST respond with a
   [RFC2510] errorMsgRep.

   If a client receives a [RFC2510] errorMsgRep (message-type 06)
   message, it MAY automatically resend the same request on the same
   connection, falling back to the [RFC2510] format; if the received
   message is not an errorMsgRep, it MUST terminate the connection.  It
   MAY then retry the communication falling back completely to the
   [RFC2510] format.

   Naturally, a client MUST abort the connection attempt if the server
   does not support any of the client's supported versions.  It SHOULD
   retry the version negotiation after a delay to check if the server
   was updated.

3.3.  Flags

   The LSB of the Flags field is used to indicate a connection close;
   all other bits in the Flags octet MUST be ignored by receivers, and
   MUST be set to zero by senders.

3.3.1.  Connection Close Flag

   By default connections are kept open after the receipt of a response.
   Either party (client or server) MAY set the connection close bit at
   any time.  If the connection close bit is set on a request, then the
   server MUST set the bit in the response and close the connection
   after sending the response.  If the bit is set on a response from the
   server, the client MUST NOT send any further requests on that
   connection.  Applications MAY decide to close an idle connection (one
   on which no response is outstanding) after some time-out.  Because of
   the problem where a client sends a request and the server closes the
   connection while the request is still in flight, clients SHOULD
   automatically retry a request for which no part of the response could
   be read due to a connection close or reset.

   If the connection is kept open, it MUST only be used for subsequent
   request/response transactions started by the client - the server MUST
   NOT use it to send requests to the client.  Different transactions
   may be freely interwoven on the same connection.  E.g. a CR/CP need
   not immediately be followed by the Confirm, but may be followed by
   any other request from a different transaction.



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3.4.  Message-Types

   Message-Types 0-127 are reserved and are to be issued under IANA
   auspices.  Message-types 128-255 are reserved for application use.

   The Message-Types currently defined are:

     ID Value   Message Name
     --------   ------------
      '00'H      pkiReq
      '01'H      pollRep
      '02'H      pollReq
      '03'H      finRep
      '05'H      pkiRep
      '06'H      errorMsgRep

   If a server receives an unknown message-type, it MUST reply with an
   InvalidMessageType errorMsgRep.  If a client receives an unknown
   message-type, it MUST abort the current CMP transaction and terminate
   the connection.

   The different TCP-Message-types are discussed in the following
   sections:

3.4.1.  pkiReq

   A pkiReq message conveys a PKIMessage from a client to a server.  The
   Value field of this TCP-Message contains a DER-encoded PKIMessage.

   The type of PKIMessages that can be carried by pkiReq TCP-Messages
   are (in the order they are defined in [RFC4210]):
      [0] Initialization Request
      [2] Certification Request
      [4] PKCS-10 Request
      [6] pop Response
      [7] Key Update Request
      [9] Key Recovery Request
      [11] Revocation Request
      [13] Cross-Certification Request
      [15] CA Key Update Announcement
      [16] Certificate Announcement
      [17] Revocation Announcement
      [18] CRL Announcement
      [20] Nested Message
      [21] General Message
      [23] Error Message





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      [24] Certificate Confirmation
      [25] Polling Request

3.4.2.  pkiRep

   TCP-Messages of this type are used to send a response to the
   requestor.  The Value field of the pkiRep contains a DER encoded
   PKIMessage.

   The type of PKIMessages that can be carried by such pkiRep messages
   are (in the order they are defined in [RFC4210]):
      [1] Initialization Response
      [3] Certification Response
      [5] pop Challenge
      [8] Key Update Response
      [10] Key Recovery Response
      [12] Revocation Response
      [14] Cross-Certificate Response
      [19] Confirmation
      [22] General Response
      [23] Error Message
      [26] Polling Response

3.4.3.  pollReq

   A pollReq is used by a client to check the status of a pending TCP-
   Message.  The Value portion of a pollReq contains:

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                       Polling-Reference                       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Polling-Reference: 32 bits (unsigned integer)
       This polling-reference MUST be the one returned via the
       respective pollRep TCP-Message.

3.4.4.  pollRep

   A pollRep is sent by the server to the client as response in case
   there is no PKIMessage ready yet.  The Value portion of the pollRep
   looks as follows:








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      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                       Polling-Reference                       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                       Time-to-Check-Back                      |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Polling-Reference: 32 bits (unsigned integer)
       A unique 32-bit number identifying the transaction.

   Time-to-Check-Back: 32 bits (unsigned integer)
       The time in seconds indicating the minimum interval after which
       the client SHOULD check the status again.  The duration for which
       the server keeps the polling-reference unique is left to the
       implementation.

3.4.5.  finRep

   A finRep is sent by the server whenever no other response applies,
   such as after receiving a CMP pkiConf.  The Value portion of the
   finRep SHALL contain:

      0 1 2 3 4 5 6 7
     +-+-+-+-+-+-+-+-+
     |     '00'H     |
     +-+-+-+-+-+-+-+-+

   '00'H: 8 bits
       All bits set to zero.

3.4.6.  errorMsgRep

   This TCP-Message is sent when a TCP-Message level protocol error is
   detected.  It is imperative that PKIError messages MUST NOT be sent
   using this message type.  Examples of TCP-Message level errors are:
   o  Invalid protocol version
   o  Invalid TCP message-type
   o  Invalid polling reference number

   The Value field of the errorMsgRep TCP-Message MUST contain:










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      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          Error-Type           |         Data-Length           |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     \                                                               \
     /                     Data  (variable length)                   /
     \                                                               \
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Error-Type: 16 bits  A value (format described below) indicating the
       type of the error.

   Data-Length: 16 bits (unsigned integer)  Contains the length of the
       Data field in number of octets.  Error messages not conveying
       additional information MUST set Data-Length to 0.

   Data: <data-length> octets
       An UTF8 text string for user readable error messages, containing
       additional information about the error.  Note that it does not
       contain a terminating NULL character at the end.  It SHOULD
       include an [RFC4646] language tag, as described in [RFC2482]

   The Error-Type is in the format MMNN where M and N are hex digits
   (0-F) and MM represents the major category and NN the minor.  The
   major categories defined by this specification are:

     ID Value   Major Categories
     --------   ----------------
      '01'H      TCP-Message version negotiation
      '02'H      client errors
      '03'H      server errors

   The major categories '80'H-'FF'H are reserved for application use.

   The different error-types are discussed in the following sections:

3.4.6.1.  VersionNotSupported

   The VersionNotSupported errorMsgRep is defined as follows:











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               +------------------+------------------------+
               | Field            | Value                  |
               +------------------+------------------------+
               | Error-Type       | '0101'H                |
               |                  |                        |
               | Data-Length      | 1                      |
               |                  |                        |
               | Data             | <version>              |
               |                  |                        |
               | UTF8-text String | implementation defined |
               +------------------+------------------------+

   where <version> is the highest TCP-Message protocol version the
   server supports.

3.4.6.2.  GeneralClientError

   The GeneralClientError errorMsgRep is defined as follows:

               +------------------+------------------------+
               | Field            | Value                  |
               +------------------+------------------------+
               | Error-Type       | '0200'H                |
               |                  |                        |
               | Data-Length      | 0                      |
               |                  |                        |
               | Data             | <empty>                |
               |                  |                        |
               | UTF8-text String | implementation defined |
               +------------------+------------------------+

3.4.6.3.  InvalidMessageType

   The InvalidMessageType errorMsgRep is defined as follows:

               +------------------+------------------------+
               | Field            | Value                  |
               +------------------+------------------------+
               | Error-Type       | '0201'H                |
               |                  |                        |
               | Data-Length      | 1                      |
               |                  |                        |
               | Data             | <message-type>         |
               |                  |                        |
               | UTF8-text String | implementation defined |
               +------------------+------------------------+

   where <message-type> is the invalid Message-Type ID received by the



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   server.

3.4.6.4.  InvalidPollID

   The InvalidPollID errorMsgRep is defined as follows:

               +------------------+------------------------+
               | Field            | Value                  |
               +------------------+------------------------+
               | Error-Type       | '0202'H                |
               |                  |                        |
               | Data-Length      | 4                      |
               |                  |                        |
               | Data             | <polling-reference>    |
               |                  |                        |
               | UTF8-text String | implementation defined |
               +------------------+------------------------+

   where <polling-reference> is the polling-reference received by the
   server, identifying the transaction.

3.4.6.5.  GeneralServerError

   The GeneralServerError errorMsgRep is defined as follows:

               +------------------+------------------------+
               | Field            | Value                  |
               +------------------+------------------------+
               | Error-Type       | '0300'H                |
               |                  |                        |
               | Data-Length      | 0                      |
               |                  |                        |
               | Data             | <empty>                |
               |                  |                        |
               | UTF8-text String | implementation defined |
               +------------------+------------------------+















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4.  HTTP-Based Protocol

   The stateless HTTP MAY be utilized for conveying CMP messages instead
   of or additionally to the TCP-Messages.

4.1.  HTTP Versions

   Either HTTP/1.0 as described in [RFC1945] or HTTP/1.1 as in [RFC2616]
   MAY be used.  Naturally, the newer version SHOULD be preferred.
   Both, server and client implementations MUST be able to interact with
   counterparts primarily utilizing the different HTTP protocol version.

4.2.  General Form

   An ASN.1 DER-encoded PKIMessage is sent as the entity-body of an HTTP
   POST request.  If the HTTP request is successful, the server returns
   the CMP reply in the body of the HTTP response.  The response status
   code in this case MUST be 200; other 2xx codes MUST NOT be used for
   this purpose.

   Note that a server may return any 1xx, 3xx, 4xx, or 5xx code if the
   HTTP request needs further handling or is otherwise not acceptable.

4.3.  MIME Type

   The MIME type "application/pkixcmp" MUST be set as in the HTTP header
   when conveying a PKIMessage.

4.4.  HTTP Considerations

   In general, CMP messages are not cachable; requests and responses
   MUST include a "Cache-Control: no-cache" (and, if either side uses
   HTTP/1.0, a "Pragma: no-cache") to prevent the client from getting
   cached responses.

   Connection management is based on the HTTP provided mechanisms
   (Connection and Proxy-Connection header fields).

   While an implementation MAY make use of all defined features of the
   HTTP protocol, it SHOULD keep the protocol utilization as simple as
   possible.

   Content codings MAY be applied.

4.5.  Compatibility Issues with Legacy Implementations

   As this document was subject of multiple changes during the long
   period of time it was created in, several implementations may exist



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   using a different approach for HTTP transport.

   Thus, legacy implementations might also use an unregistered
   "application/pkixcmp-poll" MIME type as it was specified in earlier
   drafts of this document.  Here, the entity-body of an HTTP POST
   request contains a TCP-Message instead of a plain DER-encoded
   PKIMessage.  Effectively, this is conveying PKIMessage over TCP-
   Message over HTTP.











































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5.  File-Based Protocol

   A file containing a PKIMessage MUST contain only the DER encoding of
   one PKIMessage, there MUST NOT be extraneous header or trailer
   information in the file.

   Such files can be used to transport PKIMessage sequences using e.g.
   FTP.











































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6.  Mail-Based Protocol

   This subsection specifies a means for conveying ASN.1-encoded
   messages for the protocol exchanges via Internet mail [RFC2821].  A
   simple MIME object is specified as follows.

         Content-Type: application/pkixcmp
         Content-Transfer-Encoding: base64

         <<the ASN.1 DER-encoded PKIX-CMP message, base64-encoded>>

   This MIME object can be sent and received using common MIME
   processing engines and provides a simple Internet mail transport for
   PKIX-CMP messages.  Implementations MAY wish to also recognize and
   use the "application/x-pkixcmp" MIME type (specified in earlier
   versions of this document) in order to support backward compatibility
   wherever applicable.


































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7.  Security Considerations

   Three aspects need to be considered by server side implementors:

   1.  There is no security at the TCP and HTTP protocol level (unless
       tunneled via SSL/TLS) and thus TCP-Messages SHOULD NOT be used to
       change state of the transaction.  Change of state SHOULD be
       triggered by the signed PKIMessages which are carried within the
       TCP-Message.

   2.  If the server is going to be sending messages with sensitive
       information (not meant for public consumption) in the clear, it
       is RECOMMENDED that the server sends back the message directly
       and not use the pollRep.

   3.  The polling request/response mechanism can be used for all kinds
       of denial of service attacks.  It is RECOMMENDED that a server
       does not change the polling-reference between polling requests.

































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8.  References

8.1.  Normative References

   [RFC1945]  Berners-Lee, T., Fielding, R., and H. Nielsen, "Hypertext
              Transfer Protocol -- HTTP/1.0", RFC 1945, May 1996.

   [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.

   [RFC2616]  Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
              Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
              Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

   [RFC4210]  Adams, C., Farrell, S., Kause, T., and T. Mononen,
              "Internet X.509 Public Key Infrastructure Certificate
              Management Protocol (CMP)", RFC 4210, September 2005.

   [RFC4646]  Phillips, A. and M. Davis, "Tags for Identifying
              Languages", BCP 47, RFC 4646, September 2006.

8.2.  Informative References

   [RFC2482]  Whistler, K. and G. Adams, "Language Tagging in Unicode
              Plain Text", RFC 2482, January 1999.

   [RFC2821]  Klensin, J., "Simple Mail Transfer Protocol", RFC 2821,
              April 2001.



















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Appendix A.  Acknowledgments

   The authors gratefully acknowledge the contributions of various
   members of the IETF PKIX Working Group and the ICSA CA-talk mailing
   list (a list solely devoted to discussing CMP interoperability
   efforts).













































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Appendix B.  Registration of the application/pkixcmp Media Type


















































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   To: ietf-types@iana.org
   Subject: Registration of MIME media type application/pkixcmp

   MIME media type name: application

   MIME subtype name: pkixcmp

   Required parameters: -

   Optional parameters: -

   Encoding considerations:

   Content may contain arbitrary octet values (the ASN.1 DER encoding
   of a PKIMessage sequence, as defined in the IETF PKIX Working Group
   specifications).  base64 encoding is required for MIME e-mail; no
   encoding is necessary for HTTP.

   Security considerations:

   This MIME type may be used to transport Public-Key Infrastructure
   (PKI) messages between PKI entities.  These messages are defined by
   the IETF PKIX Working Group and are used to establish and maintain
   an Internet X.509 PKI.  There is no requirement for specific
   security mechanisms to be applied at this level if the PKI messages
   themselves are protected as defined in the PKIX specifications.

   Interoperability considerations: -

   Published specification: this document

   Applications which use this media type: Applications using
   certificate management, operational, or ancillary protocols (as
   defined by the IETF PKIX Working Group) to send PKI message via
   E-Mail or HTTP.

   Additional information:

     Magic number (s): -
     File extension (s): ".PKI"
     Macintosh File Type Code (s): -

   Person and email address to contact for further information:
   Martin Peylo, martin.peylo@nsn.com

   Intended usage: COMMON

   Author/Change controller: Martin Peylo



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Authors' Addresses

   Amit Kapoor
   Certicom
   25801 Industrial Blvd
   Hayward, CA
   US

   Email: amit@trustpoint.com


   Ronald Tschalaer
   Certicom
   25801 Industrial Blvd
   Hayward, CA
   US

   Email: ronald@trustpoint.com


   Tomi Kause
   SSH Communications Security Corp.
   Fredrikinkatu 42
   Helsinki  00100
   Finland

   Email: toka@ssh.com


   Martin Peylo
   Nokia Siemens Networks
   Linnoitustie 6
   Espoo  02600
   Finland

   Email: martin.peylo@nsn.com















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