Network Working Group                                           L. Blunk
Internet-Draft                                                  M. Karir
Intended status: Standards Track                           Merit Network
Expires: August 28, 2008                                     C. Labovitz
                                                          Arbor Networks
                                                       February 25, 2008


                 MRT routing information export format
                       draft-ietf-grow-mrt-07.txt

Status of this Memo

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   applicable patent or other IPR claims of which he or she is aware
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   This Internet-Draft will expire on August 28, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2008).












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Abstract

   This document describes the MRT format for routing information
   export.  This format was developed in concert with the Multi-threaded
   Routing Toolkit (MRT) from whence the format takes it name.  The
   format can be used to export routing protocol messages, state
   changes, and routing information base contents.


Table of Contents

   1.  Requirements notation  . . . . . . . . . . . . . . . . . . . .  4
   2.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5
   3.  Basic MRT Format . . . . . . . . . . . . . . . . . . . . . . .  6
   4.  MRT Informational Types  . . . . . . . . . . . . . . . . . . .  8
     4.1.  NULL Type  . . . . . . . . . . . . . . . . . . . . . . . .  8
     4.2.  START Type . . . . . . . . . . . . . . . . . . . . . . . .  8
     4.3.  DIE Type . . . . . . . . . . . . . . . . . . . . . . . . .  8
     4.4.  I_AM_DEAD Type . . . . . . . . . . . . . . . . . . . . . .  8
     4.5.  PEER_DOWN Type . . . . . . . . . . . . . . . . . . . . . .  9
   5.  MRT Routing Information Types  . . . . . . . . . . . . . . . . 10
     5.1.  BGP Type . . . . . . . . . . . . . . . . . . . . . . . . . 10
       5.1.1.  BGP_NULL Subtype . . . . . . . . . . . . . . . . . . . 10
       5.1.2.  BGP_UPDATE Subtype . . . . . . . . . . . . . . . . . . 11
       5.1.3.  BGP_PREF_UPDATE Subtype  . . . . . . . . . . . . . . . 11
       5.1.4.  BGP_STATE_CHANGE Subtype . . . . . . . . . . . . . . . 11
       5.1.5.  BGP_SYNC Subtype . . . . . . . . . . . . . . . . . . . 12
       5.1.6.  BGP_OPEN Subtype . . . . . . . . . . . . . . . . . . . 12
       5.1.7.  BGP_NOTIFY Subtype . . . . . . . . . . . . . . . . . . 12
       5.1.8.  BGP_KEEPALIVE Subtype  . . . . . . . . . . . . . . . . 12
     5.2.  RIP Type . . . . . . . . . . . . . . . . . . . . . . . . . 13
     5.3.  IDRP Type  . . . . . . . . . . . . . . . . . . . . . . . . 13
     5.4.  RIPNG Type . . . . . . . . . . . . . . . . . . . . . . . . 13
     5.5.  BGP4PLUS and BGP4PLUS_01 Types . . . . . . . . . . . . . . 13
     5.6.  OSPF Type  . . . . . . . . . . . . . . . . . . . . . . . . 14
     5.7.  TABLE_DUMP Type  . . . . . . . . . . . . . . . . . . . . . 14
     5.8.  TABLE_DUMP_V2 Type . . . . . . . . . . . . . . . . . . . . 16
     5.9.  BGP4MP Type  . . . . . . . . . . . . . . . . . . . . . . . 18
       5.9.1.  BGP4MP_STATE_CHANGE Subtype  . . . . . . . . . . . . . 19
       5.9.2.  BGP4MP_MESSAGE Subtype . . . . . . . . . . . . . . . . 20
       5.9.3.  BGP4MP_ENTRY Subtype . . . . . . . . . . . . . . . . . 20
       5.9.4.  BGP4MP_SNAPSHOT Subtype  . . . . . . . . . . . . . . . 21
       5.9.5.  BGP4MP_STATE_CHANGE_AS4 Subtype  . . . . . . . . . . . 22
       5.9.6.  BGP4MP_MESSAGE_AS4 Subtype . . . . . . . . . . . . . . 22
     5.10. BGP4MP_ET Type . . . . . . . . . . . . . . . . . . . . . . 23
     5.11. ISIS Type  . . . . . . . . . . . . . . . . . . . . . . . . 23
     5.12. ISIS_ET Type . . . . . . . . . . . . . . . . . . . . . . . 23
     5.13. OSPFv3 Type  . . . . . . . . . . . . . . . . . . . . . . . 23



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     5.14. OSPFv3_ET Type . . . . . . . . . . . . . . . . . . . . . . 24
   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 25
     6.1.  Type Codes . . . . . . . . . . . . . . . . . . . . . . . . 25
     6.2.  Subtype Codes  . . . . . . . . . . . . . . . . . . . . . . 25
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 26
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 27
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 27
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 27
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 28
   Intellectual Property and Copyright Statements . . . . . . . . . . 29









































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1.  Requirements notation

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














































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2.  Introduction

   Researchers and engineers often wish to analyze network behavior by
   studying routing protocol transactions and routing information base
   snapshots.  To this end, the MRT format was developed to encapsulate,
   export, and archive this information in a standardized data
   representation.  The BGP routing protocol, in particular, has been
   the subject of extensive study and analysis which has been
   significantly aided by the availability of the MRT format.  The MRT
   format was initially defined in the MRT Programmer's Guide [MRT PROG
   GUIDE].

   This memo serves to document the MRT format as currently implemented
   in publicly available software.  The format has been extended since
   it's original introduction in the MRT toolset and these extensions
   are also included in this memo.  Further extensions may be introduced
   at a later date through additional definitions of the MRT Type field
   and Subtype fields.

   Fields which contain multi-byte numeric values are encoded in network
   byte order from most significant byte to least significant byte.
   Fields which contain routing message fields are encoded in the same
   order as they appear in the packet contents.




























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3.  Basic MRT Format

   All MRT format messages have a common header which includes a
   timestamp, Type, Subtype, and length field.  The header is followed
   by a message field.  The MRT common header is illustrated 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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                           Timestamp                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |             Type              |            Subtype            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                             Length                            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Message... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Header Field Descriptions:


      Timestamp:

         Time in seconds since 1 January 1970 00:00:00 UTC


      Type:

         A 2-octet field that indicates the Type of information
         contained in the message field.  Types 0 through 4 are
         informational messages pertaining to the state of an MRT
         collector, while Types 5 and higher are used to convey routing
         information.


      Subtype:

         A 2-octet field that is used to further distinguish message
         information within a particular message Type.


      Length:

         A 4-octet message length field.  The length field contains the
         number of bytes within the message.  The length field does not
         include the length of the MRT common header.





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      Message:

         A variable length message.  The contents of this field are
         context dependent upon the Type and Subtype fields.














































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4.  MRT Informational Types

   The MRT format defines five Informational Type messages.  These
   messages are intended to signal the state of an MRT data collector
   and do not contain routing information.  These messages are OPTIONAL
   and were largely intended for use when MRT messages are sent over a
   network to a remote repository store.  However, MRT message
   repository stores have traditionally resided on the same device as
   the collector and these Informational Types have seen limited
   implementation.  Further, transport mechanisms for MRT messages are
   considered to be outside the scope of this document.

   Two of these messages are considered potentially useful in
   implementations with a local repository.  In particular, the START
   and I_AM_DEAD messages MAY be used to provide a time reference when a
   data collector begins and ends the collection process.

   The message field MAY contain an OPTIONAL message string for
   diagnostic purposes.  The message string encoding MUST follow the
   UTF-8 transformation format.  The Subtype field is unused for these
   Types and SHOULD be set to 0.

   The MRT Informational Types are defined below:

       0    NULL         *DEPRECATED*
       1    START
       2    DIE          *DEPRECATED*
       3    I_AM_DEAD
       4    PEER_DOWN    *DEPRECATED*

4.1.  NULL Type

   The NULL Type message causes no operation and is deprecated.

4.2.  START Type

   The START Type indicates a collector is about to begin generating MRT
   messages.

4.3.  DIE Type

   The DIE Type signals a remote MRT repository it should stop accepting
   messages.  This Type is deprecated.

4.4.  I_AM_DEAD Type

   An I_AM_DEAD MRT message indicates that a collector has shut down and
   has stopped generating MRT messages.



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4.5.  PEER_DOWN Type

   The PEER_DOWN message was intended to indicate that a collector had
   lost association with a BGP peer.  However, the MRT format provides
   BGP state change message types which duplicate this functionality.
   This Type is deprecated.













































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5.  MRT Routing Information Types

   The following Types are currently defined for the MRT format.  Types
   5-12 were defined in the MRT Toolkit package.  The BGP4MP Type,
   number 16, was initially defined in the Zebra routing software
   package.  The BGP4MP_ET, ISIS, and ISIS_ET Types were initially
   defined in the Sprint Labs Python Routing Toolkit (PyRT).

       5    BGP          *DEPRECATED*
       6    RIP
       7    IDRP         *DEPRECATED*
       8    RIPNG
       9    BGP4PLUS     *DEPRECATED*
       10   BGP4PLUS_01  *DEPRECATED*
       11   OSPF
       12   TABLE_DUMP
       13   TABLE_DUMP_V2
       16   BGP4MP
       17   BGP4MP_ET
       32   ISIS
       33   ISIS_ET
       48   OSPFv3
       49   OSPFv3_ET

5.1.  BGP Type

   The BGP Type indicates the Message field contains BGP routing
   information.  The BGP routing protocol is defined in RFC 4271
   [RFC4271].  The information in the message is dependent on the
   Subtype value.  The BGP Type and all associated Subtypes are
   considered to be DEPRECATED by the BGP4MP Type.

   The following BGP Subtypes are defined for the MRT BGP Type.

       0    BGP_NULL
       1    BGP_UPDATE
       2    BGP_PREF_UPDATE
       3    BGP_STATE_CHANGE
       4    BGP_SYNC
       5    BGP_OPEN
       6    BGP_NOTIFY
       7    BGP_KEEPALIVE

5.1.1.  BGP_NULL Subtype

   The BGP_NULL Subtype is a reserved Subtype.





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5.1.2.  BGP_UPDATE Subtype

   The BGP_UPDATE Subtype is used to encode BGP UPDATE messages.  The
   format of the MRT Message field for this Subtype is as follows:

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Peer AS number        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Peer IP address                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Local AS number        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Local IP address                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP UPDATE Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The BGP UPDATE Contents include the entire BGP UPDATE message which
   follows the BGP Message Header.  The BGP Message Header itself is not
   included.  The Peer AS number and IP address fields contain the AS
   number and IP address of the remote system which are generating the
   BGP UPDATE messages.  The Local AS number and IP address fields
   contain the AS number and IP address of the local collector system
   which is archiving the messages.

5.1.3.  BGP_PREF_UPDATE Subtype

   The BGP_PREF_UPDATE Subtype is not defined.

5.1.4.  BGP_STATE_CHANGE Subtype

   The BGP_STATE_CHANGE Subtype is used to record changes in the BGP
   finite state machine.  These FSM states are defined in RFC 4271
   [RFC4271], Section 8.2.2.  Both the old state value and the new state
   value are encoded as 2-octet numbers.  The state values are defined
   numerically as follows:

       1    Idle
       2    Connect
       3    Active
       4    OpenSent
       5    OpenConfirm
       6    Established

   The format of the MRT Message field is 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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Peer AS number        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Peer IP address                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            Old State          |          New State            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.1.5.  BGP_SYNC Subtype

   The BGP_SYNC Subtype was intended to convey a system file name where
   BGP Table Dump messages should be recorded.  The View # was to
   correspond to the View # provided in the TABLE_DUMP Type messages.
   There are no known implementations of this subtype and it SHOULD be
   ignored.  The following format applies to this Subtype:

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        View #                 |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            File Name... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The File Name is terminated with a NULL (0) character.

5.1.6.  BGP_OPEN Subtype

   The BGP_OPEN Subtype is used to encode BGP OPEN messages.  The format
   of the MRT Message field for this Subtype is the same as the
   BGP_UPDATE, however, the last field contains the contents of the BGP
   OPEN message.

5.1.7.  BGP_NOTIFY Subtype

   The BGP_NOTIFY Subtype is used to encode BGP NOTIFICATION messages.
   The format of the MRT Message field for this Subtype is the same as
   the BGP_UPDATE, however, the last field contains the contents of the
   BGP NOTIFICATION message.

5.1.8.  BGP_KEEPALIVE Subtype

   The BGP_KEEPALIVE Subtype is used to encode BGP KEEPALIVE messages.
   The format of the MRT Message field for this Subtype is the same as
   the BGP_UPDATE, however, the last field contains no information.




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5.2.  RIP Type

   The RIP Type is used to export RIP protocol packets as defined in RFC
   1058 [RFC1058].  The Subtype field is currently reserved for this
   Type and SHOULD be set to 0.

   The format of the MRT Message field for the RIP Type is as follows:

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Peer IP address                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Local IP address                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    RIP Message Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.3.  IDRP Type

   The IDRP Type is used to export Inter-Domain-Routing Protocol (IDRP)
   protocol information as defined in the ISO/IEC 10747 standard.  The
   Subtype field is unused.  This Type is deprecated due to lack of
   deployment of IDRP.

5.4.  RIPNG Type

   The RIPNG Type is used to export RIPNG protocol packets as defined in
   RFC 2080 [RFC2080].  The Subtype field is currently reserved for this
   Type and SHOULD be set to 0.

   The format of the MRT Message field for the RIPNG Type is as follows:

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Peer IP address                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Local IP address                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                  RIPNG Message Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.5.  BGP4PLUS and BGP4PLUS_01 Types

   The BGP4PLUS and BGP4PLUS_01 Types were defined to support IPv6 BGP
   routing information.  The BGP4PLUS Type was specified based on the
   initial Internet Draft for Multiprotocol Extensions to BGP-4.  The



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   BGP4PLUS_01 Type was specified to correspond to the -01 revision of
   this Internet Draft.  The two Types share the same definitions in
   terms of their MRT format specifications.

   The Subtype field definitions are shared with the BGP Type, however,
   the address fields in the BGP_UPDATE, BGP_OPEN, BGP_NOTIFY,
   BGP_KEEPALIVE, and BGP_STATE_CHANGE Subtype messages are extended to
   16 octets for IPv6 addresses.  As with the BGP Type, the BGP4PLUS and
   BGP4PLUS_01 Types are deprecated as they superseded by the BGP4MP
   Type.

5.6.  OSPF Type

   This Type supports the OSPF Protocol as defined in RFC 2328
   [RFC2328].  The Subtype field may contain two possible values:

       0    OSPF_STATE_CHANGE
       1    OSPF_LSA_UPDATE

   The format of the MRT Message field for the OSPF Type is as follows:

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Remote IP address                     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Local IP address                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                  OSPF Message Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.7.  TABLE_DUMP Type

   The TABLE_DUMP Type is used to encode the contents of a BGP Routing
   Information Base (RIB).  Each RIB entry is encoded in a distinct
   sequential MRT record.  The Subtype field is used to encode whether
   the RIB entry contains IPv4 or IPv6 addresses.  There are two
   possible values for the Subtype as shown below.

       1    AFI_IPv4
       2    AFI_IPv6

   The format of the TABLE_DUMP Type is illustrated below.








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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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |           View #              |       Sequence number         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Prefix (variable)                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       | Prefix Length |    Status     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Originated Time                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    Peer IP address (variable)                 |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |           Peer AS             |       Attribute Length        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   BGP Attribute... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The View field is normally 0 and is intended for cases where an
   implementation may have multiple RIB views (such as a route server).
   The Sequence field is a simple incremental counter for each RIB
   entry.  A typical RIB dump will exceed the 16-bit bounds of this
   counter and implementation should simply wrap back to zero and
   continue incrementing the counter in such cases.

   The Prefix field contains the IP address of a particular RIB entry.
   The size of this field is dependent on the value of the Subtype for
   this message.  For AFI_IPv4, this field is 4 octets, for AFI_IPv6, it
   is 16 octets in length.  The Prefix Length field indicates the length
   in bits of the prefix mask for the preceding Prefix field.

   The Status octet is not used in the TABLE_DUMP Type and SHOULD be set
   to 1.

   The Originated Time contains the 4-octet time at which this prefix
   was heard.  The value represents the time in seconds since 1 January
   1970 00:00:00 UTC.

   The Peer IP field is the IP address of the peer which provided the
   update for this RIB entry.  As with the Prefix field, the size of
   this field is dependent on the Subtype.  AFI_IPv4 indicates a 4 octet
   field and an IPv4 address, while a Subtype of AFI_IPv6 requires a 16
   octet field and an IPv6 address.  The Peer AS field contains the AS
   number of the peer.

   Attribute length is the length of Attribute field and is 2-octets.
   The Attribute field contains the attribute information for the RIB
   entry.



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5.8.  TABLE_DUMP_V2 Type

   The TABLE_DUMP_V2 Type updates the TABLE_DUMP Type to include 32BIT
   ASN support and full support for BGP Multiprotocol extensions.  It
   also improves upon the space efficiency of the TABLE_DUMP Type by
   employing an index table for peers and permitting a single MRT record
   per NLRI entry.  The following subtypes are used with the
   TABLE_DUMP_V2 Type.

       1    PEER_INDEX_TABLE
       2    RIB_IPV4_UNICAST
       3    RIB_IPV4_MULTICAST
       4    RIB_IPV6_UNICAST
       5    RIB_IPV6_MULTICAST
       6    RIB_GENERIC

   An initial PEER_INDEX_TABLE MRT record provides the BGP ID of the
   collector, an optional view name, and a list of indexed peers.
   Following the PEER_INDEX_TABLE MRT record, a series of MRT records
   are used to encode RIB table entries.  This series of MRT records use
   subtypes 2-6 and are separate from the PEER_INDEX_TABLE MRT record
   itself and include full MRT record headers.  The header of the
   PEER_INDEX_TABLE Subtype is shown below.  The View Name is optional
   and, if not present, the View Name Length MUST be set to 0.  The View
   Name encoding MUST follow the UTF-8 transformation format.

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Collector BGP ID                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |       View Name Length        |     View Name (variable)      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |          Peer Count           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The format of the peer entries is shown below.  The PEER_INDEX_TABLE
   record contains Peer Count peer entries.













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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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |   Peer Type   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Peer BGP ID                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   Peer IP address (variable)                  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Peer AS (variable)                     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The Peer Type, Peer BGP ID, Peer IP, and Peer AS fields are repeated
   as indicated by the Peer Count field.  The position of the Peer in
   the PEER_INDEX_TABLE is used as an index in the subsequent
   TABLE_DUMP_V2 MRT records.  The index number begins with 0.

   The Peer Type field is a bit field which encodes the type of the AS
   and IP address as follows:

      Bit 0 - unset for IPv4 Peer IP address, set for IPv6
      Bit 1 - unset when Peer AS field is 16 bits, set when it's 32 bits

   The records which follow the PEER_INDEX_TABLE record constitute the
   RIB entries and include a header which specifies a sequence number,
   NLRI, and a count of the number of RIB entries which follow.

   The format for the RIB_IPV4_UNICAST, RIB_IPV4_MULTICAST,
   RIB_IPV6_UNICAST, and RIB_IPV6_MULTICAST headers are shown below.
   The Prefix Length and Prefix fields are encoded in the same manner as
   the BGP NLRI encoding for IPV4 and IPV6 prefixes.  Namely, the Prefix
   field contains address prefixes followed by enough trailing bits to
   make the end of the field fall on an octet boundary.  Note that the
   value of trailing bits is irrelevant.

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Sequence number                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       | Prefix Length |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Prefix (variable)                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Entry Count           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The RIB_GENERIC header is shown below.  It includes Address Family



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   Identifier (AFI), Subsequent AFI and a single NLRI entry.  The NLRI
   information is specific to the AFI and SAFI values.  An
   implementation which does not recognize particular AFI and SAFI
   values SHOULD discard the remainder of the MRT record.

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Sequence number                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Address Family Identifier  |Subsequent AFI |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |     Network Layer Reachability Information (variable)         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Entry Count           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The RIB entry headers are followed by a series of RIB entries which
   are repeated Entry Count times.  These entries share a common format
   as shown below.  They include a Peer Index from the PEER_INDEX_TABLE
   MRT record, an originated time for the RIB entry, and the BGP path
   attribute length and attributes encoded as provided in a BGP Update
   message.

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Peer Index            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Originated Time                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |      Attribute Length         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP Attributes... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   There is one exception to the encoding of BGP attributes for the BGP
   MP_REACH_NLRI attribute (BGP Type Code 14) [RFC 4760].  Since the
   AFI, SAFI, and NLRI information is already encoded in the
   MULTIPROTOCOL header, only the Next Hop Address Length and Next Hop
   Address fields are included.  The Reserved field is omitted.  The
   attribute length is also adjusted to reflect only the length of the
   Next Hop Address Length and Next Hop Address fields.

5.9.  BGP4MP Type

   This Type was initially defined in the Zebra software package for the
   BGP protocol with multiprotocol extension support as defined by RFC



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   4760 [RFC4760].  It supersedes the BGP, BGP4PLUS, BGP4PLUS_01 Types.
   The BGP4MP Type has six Subtypes which are defined as follows:

       0    BGP4MP_STATE_CHANGE
       1    BGP4MP_MESSAGE
       2    BGP4MP_ENTRY                  *DEPRECATED*
       3    BGP4MP_SNAPSHOT               *DEPRECATED*
       4    BGP4MP_STATE_CHANGE_AS4
       5    BGP4MP_MESSAGE_AS4

5.9.1.  BGP4MP_STATE_CHANGE Subtype

   This record is used to encode state changes in the BGP finite state
   machine.  As with the BGP_STATE_CHANGE Subtype, the BGP FSM states
   are encoded in the Old State and New State fields to indicate the
   previous and current state.  The format is illustrated 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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Peer AS number        |        Local AS number        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Interface Index        |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Peer IP address (variable)               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Local IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            Old State          |          New State            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   While BGP4MP_STATE_CHANGE message is similar to the BGP_STATE_CHANGE
   message, it also includes interface index and Address Family fields.
   As with the BGP_STATE_CHANGE message, the FSM states are defined in
   RFC 4271 [RFC4271], Section 8.2.2 with the numeric values for these
   states defined inthe BGP_STATE_CHANGE section.  The interface index
   provides the interface number of the peering session.  The index
   value is OPTIONAL and MAY be zero if unknown or unsupported.  The
   Address Family indicates what types of addresses are in the the
   address fields.  At present, the following AFI Types are supported:

       1    AFI_IPv4
       2    AFI_IPv6








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5.9.2.  BGP4MP_MESSAGE Subtype

   This Subtype is used to encode BGP Messages.  It is similar to the
   BGP_UPDATE Subtype, except that is can be used to encode any Type of
   message (not simply BGP UPDATES).  In order to determine the BGP
   message Type, the entire BGP message is included in the BGP Message
   field.  This includes 16-octet marker, 2-ocet length, and 1-octet
   type fields.  Note that the BGP4MP_MESSAGE Subtype does not support
   32BIT AS numbers nor IPv6 addresses.  The BGP4MP_MESSAGE_AS4 Subtype
   updates the BGP4MP_MESSAGE Subtype in order to support these.  The
   BGP4MP_MESSAGE fields are 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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Peer AS number        |        Local AS number        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Interface Index        |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Peer IP address (variable)               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Local IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP Message... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The interface index provides the interface number of the peering
   session.  The index value is OPTIONAL and MAY be zero if unknown or
   unsupported.  The Address Family indicates what types of addresses
   are in the the subsequent address fields.  At present, the following
   AFI Types are supported:

       1    AFI_IPv4
       2    AFI_IPv6

   Note that the Address Family value only applies to the IP addresses
   contained in the MRT header.  The BGP4MP_MESSAGE Subtype is otherwise
   transparent to the contents of the actual message which may contain
   any valid AFI/SAFI values.  Only one BGP message may be encoded in
   the BGP4MP_MESSAGE Subtype.

5.9.3.  BGP4MP_ENTRY Subtype

   This Subtype is similar to the TABLE_DUMP Type and is used to record
   RIB table entries.  It extends the TABLE_DUMP Type to include true
   multiprotocol support.  However, this Type does not support 32BIT AS
   numbers and has not been widely implemented.  This Type is deprecated
   in favor of the TABLE_DUMP_V2 which includes 32BIT AS number support



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   and a more compact format.

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Peer AS number        |        Local AS number        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Interface Index        |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Peer IP address (variable)               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Local IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |           View #              |             Status            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Time last change                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Address Family         |    SAFI       | Next-Hop-Len  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Next Hop Address (variable)               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       | Prefix Length  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Address Prefix (variable)                 |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |       Attribute Length        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP Attribute... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.9.4.  BGP4MP_SNAPSHOT Subtype

   This Subtype was intended to convey a system file name where
   BGP4MP_ENTRY messages should be recorded.  It is similar to the
   BGP_SYNC message Subtype and is deprecated.

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        View #                 |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            File Name... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+








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5.9.5.  BGP4MP_STATE_CHANGE_AS4 Subtype

   This Subtype updates the BGP4MP_STATE_CHANGE Subtype to support 32BIT
   Autonomous System numbers.  As with the BGP4MP_STATE_CHANGE Subtype,
   the BGP FSM states are encoded in the Old State and New State fields
   to indicate the previous and current state.  Aside from the extension
   of the peer and local AS fields to 32 bits, this subtype is otherwise
   identical to the BGP4MP_STATE_CHANGE Subtype.  The
   BGP4MP_STATE_CHANGE_AS4 fields are 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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Peer AS number                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Local AS number                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Interface Index        |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Peer IP address (variable)               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Local IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            Old State          |          New State            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.9.6.  BGP4MP_MESSAGE_AS4 Subtype

   This Subtype updates the BGP4MP_MESSAGE Subtype to support 32BIT
   Autonomous System numbers.  The BGP4MP_MESSAGE_AS4 Subtype is
   otherwise identical to the BGP4MP_MESSAGE Subtype.  The
   BGP4MP_MESSAGE_AS4 fields are 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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Peer AS number                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Local AS number                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Interface Index        |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Peer IP address (variable)               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Local IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP Message... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



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5.10.  BGP4MP_ET Type

   This Type was initially defined in the Sprint Labs Python Routing
   Toolkit (PyRT).  It extends the MRT common header field to include a
   32BIT microsecond timestamp field.  The type and subtype field
   definitions remain as defined for the BGP4MP Type.  The 32BIT
   microsecond timestamp immediately follows the length field in the MRT
   common header and precedes all other fields in the message.  The
   32BIT microsecond field is included in the computation of the length
   field value.  The MRT common header modification is illustrated
   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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                           Timestamp                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |             Type              |            Subtype            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                             Length                            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      microsecond timestamp                    |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Message... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.11.  ISIS Type

   This Type was initially defined in the Sprint Labs Python Routing and
   supports the IS-IS routing protocol as defined in RFC 1195 [RFC1195].
   There is no Type specific header for the ISIS Type.  The Subtype code
   for this Type is undefined.  The ISIS PDU directly follows the MRT
   common header fields.

5.12.  ISIS_ET Type

   The ISIS_ET Type extends the ISIS Type to support microsecond
   timestamps.  As with the BGP4MP_ET Type, a 32BIT microsecond
   timestamp field is appended to the MRT common header after the length
   field.  The ISIS_ET Type is otherwise identical to the ISIS Type.

5.13.  OSPFv3 Type

   The OSPFv3 Type extends the original OSPF Type to support IPv6
   addresses for the OSPFv3 protocol as defined in RFC 2740 [RFC2740].
   The format of the MRT Message field for the OSPFv3 Type is 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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Remote IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Local IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                  OSPF Message Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.14.  OSPFv3_ET Type

   The OSPFv3_ET Type extends the OSPFv3 Type to support microsecond
   timestamps.  As with the BGP4MP_ET Type, a 32BIT microsecond
   timestamp field is appended to the MRT common header after the length
   field and its length is included in the calculation of the length
   field value.  The OSPFv3_ET Type is otherwise identical to the OSPFv3
   Type.































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6.  IANA Considerations

   This section provides guidance to the Internet Assigned Numbers
   Authority (IANA) regarding registration of values related to the MRT
   specification, in accordance with BCP 26, RFC 2434 [RFC2434].

   There are two name spaces in MRT that require registration: Type
   Codes and Subtype Codes.

   MRT is not intended as a general-purpose specification for protocol
   information export, and allocations should not be made for purposes
   unrelated to routing protocol information export.

   The following policies are used here with the meanings defined in BCP
   26: "Specification Required", "IETF Consensus".

6.1.  Type Codes

   Type Codes have a range from 0 to 65535, of which 0-64 have been
   allocated.  New Type Codes MUST be allocated starting at 65.  Type
   Codes 65 - 32767 are to be assigned by IETF Consensus.  Type Codes
   32768 - 65535 are assigned based on Specification Required.

6.2.  Subtype Codes

   Subtype Codes have a range from 0 to 65535.  Subtype definitions are
   specific to a particular Type Code definition.  New Subtype Code
   definition must reference an existing Type Code to which the Subtype
   belongs.  As Subtype Codes are specific to Type Codes, new numbers
   must be unique for the particular Type Code to which the Subtype
   applies.  Subtype Codes specific to the Type Codes 0 - 32767 are
   assigned by IETF Consensus.  Subtype Codes specific to Type Codes
   32768 - 65535 are assigned based on Specification Required.


















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7.  Security Considerations

   The MRT Format utilizes a structure which can store routing protocol
   information data.  The fields defined in the MRT specification are of
   a descriptive nature and provide information that is useful to
   facilitate the analysis of routing data.  As such, the fields
   currently defined in the MRT specification do not in themselves
   create additional security risks, since the fields are not used to
   induce any particular behavior by the recipient application.










































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8.  References

8.1.  Normative References

   [RFC1058]  Hedrick, C., "Routing Information Protocol", RFC 1058,
              June 1988.

   [RFC1195]  Callon, R., "Use of OSI IS-IS for routing in TCP/IP and
              dual environments", RFC 1195, December 1990.

   [RFC2080]  Malkin, G. and R. Minnear, "RIPng for IPv6", RFC 2080,
              January 1997.

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

   [RFC2328]  Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.

   [RFC2434]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 2434,
              October 1998.

   [RFC2740]  Coltun, R., Ferguson, D., and J. Moy, "OSPF for IPv6",
              RFC 2740, December 1999.

   [RFC4271]  Rekhter, Y., Li, T., and S. Hares, "A Border Gateway
              Protocol 4 (BGP-4)", RFC 4271, January 2006.

   [RFC4760]  Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
              "Multiprotocol Extensions for BGP-4", RFC 4760,
              January 2007.

8.2.  Informative References

   [MRT PROG GUIDE]
              Labovitz, C., "MRT Programmer's Guide", November 1999,
              <http://www.merit.edu/networkresearch/mrtprogrammer.pdf>.














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Authors' Addresses

   Larry Blunk
   Merit Network

   Email: ljb@merit.edu


   Manish Karir
   Merit Network

   Email: mkarir@merit.edu


   Craig Labovitz
   Arbor Networks

   Email: labovit@arbor.net

































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Full Copyright Statement

   Copyright (C) The IETF Trust (2008).

   This document is subject to the rights, licenses and restrictions
   contained in BCP 78, and except as set forth therein, the authors
   retain all their rights.

   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
   THE INTERNET ENGINEERING TASK FORCE DISCLAIM 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.


Intellectual Property

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
   made any independent effort to identify any such rights.  Information
   on the procedures with respect to rights in RFC documents can be
   found in BCP 78 and BCP 79.

   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use of
   such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at
   http://www.ietf.org/ipr.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at
   ietf-ipr@ietf.org.


Acknowledgment

   Funding for the RFC Editor function is provided by the IETF
   Administrative Support Activity (IASA).





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