rfc3025.txt

最新的RFC

Network Working Group                                         G. Dommety
Request for Comments: 3025                                      K. Leung
Category: Standards Track                                  cisco Systems
                                                           February 2001


           Mobile IP Vendor/Organization-Specific Extensions

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

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

Abstract

   This document defines two new extensions to Mobile IP.  These
   extensions will facilitate equipment vendors and organizations to
   make specific use of these extensions as they see fit for research or
   deployment purposes.

1. Introduction

   Current specification of Mobile IP [1] does not allow for
   organizations and vendors to include organization/vendor-specific
   information in the Mobile IP messages.  With the imminent wide scale
   deployment of Mobile IP it is useful to have vendor or organization-
   Specific Extensions to support this capability.  This document
   defines two extensions that can be used for making organization
   specific extensions by vendors/organizations for their own specific
   purposes.

1.1. Specification Language

   The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [3].

   In addition, the following words are used to signify the requirements
   of the specification.





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RFC 3025          Mobile IP Vendor Specific Extensions     February 2001


   silently discard
            The implementation discards the datagram without further
            processing, and without indicating an error to the sender.
            The implementation SHOULD provide the capability of logging
            the error, including the contents of the discarded datagram,
            and SHOULD record the event in a statistics counter.

2. Vendor/Organization Specific Extensions

   Two Vendor/Organization Specific Extensions are described, Critical
   (CVSE) and Normal (NVSE) Vendor/Organization Specific Extensions.
   The basic differences between the Critical and Normal Extensions are
   that when the Critical extension is encountered but not recognized,
   the message containing the extension MUST be silently discarded,
   whereas when a Normal Vendor/Organization Specific Extension is
   encountered but not recognized, the extension SHOULD be ignored, but
   the rest of the Extensions and message data MUST still be processed.
   Another difference between the two is that Critical
   Vendor/Organization Extension has a length field of two octets and
   the NVSE has a length field of only one octet.

2.1. Critical Vendor/Organization Specific Extension (CVSE)

   The format of this extension is as 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |   Reserved    |            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        Vendor/Org-ID                          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Vendor-CVSE-Type     |    Vendor-CVSE-Value ...
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         Figure 1: Critical Vendor/Organization Specific Extension

   Type       CVSE-TYPE-NUMBER 37

   Reserved   Reserved for future use.  MUST be set to 0 on sending,
              MUST be ignored on reception.

   Length     Length in bytes of this extension, not including the Type
              and Length bytes.







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RFC 3025          Mobile IP Vendor Specific Extensions     February 2001


   Vendor/Org-ID
              The high-order octet is 0 and the low-order 3 octets are
              the SMI Network Management Private Enterprise Code of the
              Vendor in network byte order, as defined in the Assigned
              Numbers RFC [2].

   Vendor-CVSE-Type
              Indicates the particular type of Vendor-CVSE-Extension.
              The administration of the Vendor-CVSE-Types is done by the
              Vendor.

   Vendor-CVSE-Value
              Vendor/organization specific data of this Vendor-CVSE-
              Extension.  These data fields may be published in future
              RFCs.  The Vendor-CVSE-Value is zero or more octets.  The
              length of this field can be computed from the Length Field
              Value.

   If an implementation does not recognize the CVSE, according to RFC
   2002 [1], the entire packet is to be silently dropped.

2.2. Normal Vendor/Organization Specific Extension (NVSE)

   The format of this extension is as 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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |    Length     |               Reserved        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Vendor/Org-ID                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    Vendor-NVSE-Type           | Vendor-NVSE-Value ...
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

          Figure 2: Normal Vendor/Organization Specific Extension

   Type       NVSE-TYPE-NUMBER 133

   Length     Length in bytes of this extension, not including the Type
              and Length bytes.

   Reserved   Reserved for future use.  To be set to 0.








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RFC 3025          Mobile IP Vendor Specific Extensions     February 2001


   Vendor/Org-ID
              The high-order octet is 0 and the low-order 3 octets are
              the SMI Network Management Private Enterprise Code of the
              Vendor in network byte order, as defined in the Assigned
              Numbers RFC [2].

   Vendor-NVSE-Type Indicates the particular type of Vendor-NVSE-
              Extension. The administration of the Vendor-NVSE-Types is
              done by the Vendor.

   Vendor-NVSE-Value
              Vendor/organization specific data of this Vendor-NVSE-
              Extension.  These data fields may be published in future
              RFCs.  The Vendor-NVSE-Value is zero or more octets.  The
              length  of this field can be computed from the Length
              Field Value.

2.3 Vendor/Organization Specific Extensions Processing Considerations

   When a Mobile IP entity receives a registration request message (or
   any other request/update message) with an extension of type CVSE-
   TYPE-NUMBER and recognizes it, but the extension contains an
   unknown/unsupported vendor ID or Vendor-CVSE-Type, a registration
   reject (or the appropriate deny message) MUST be sent with the error
   code to indicate that the registration was rejected due to the
   presence of an unknown CVSE.

   When a Mobile IP entity receives a registration reply (or any other
   mobile IP reply/acknowledgement message) with an extension of type
   CVSE-TYPE-NUMBER and recognizes it, but the extensions contains an
   unknown/unsupported vendor ID or Vendor-CVSE-Type, the processing is
   performed as described below.

   1. If the Mobile IP entity is a transit node for the reply (i.e.,
   this entity processes and sends the registration reply to another
   entity) a registration reject (or the appropriate deny message) MUST
   be sent with the error code to indicate that the registration was
   rejected due to the presence of an unknown CVSE.  For example, FA
   when it receives an unknown CVSE in a registration reply from the HA,
   should send a registration reject to the MN.

   2. If the Mobile IP entity is not a transit node for the reply, the
   reply is treated as a reject (or the appropriate deny message) due to
   the presence of an unknown CVSE.







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