Global Routing Operations                                     P. Lucente
Internet-Draft                                                       NTT
Updates: 7854 (if approved)                                        Y. Gu
Intended status: Standards Track                                  Huawei
Expires: 21 July 2025                                    17 January 2025


  BMP v4: TLV support for BMP Route Monitoring and Peer Down Messages
                       draft-ietf-grow-bmp-tlv-15

Abstract

   Most of the message types defined by the BGP Monitoring Protocol
   (BMP) make provision for data in TLV format.  However, Route
   Monitoring messages (which provide a snapshot of the monitored
   Routing Information Base) and Peer Down messages (which indicate that
   a peering session was terminated) do not.  Supporting (optional) data
   in TLV format across all BMP message types allows for a homogeneous
   and extensible structure that would be useful for the most different
   use-cases that need to convey additional data to a BMP station.
   While it is not intended for this document to cover any specific
   utilization scenario, it defines a consistent and simple way to
   support TLV data in all message types.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 21 July 2025.

Copyright Notice

   Copyright (c) 2025 IETF Trust and the persons identified as the
   document authors.  All rights reserved.






Lucente & Gu              Expires 21 July 2025                  [Page 1]

Internet-Draft                   BMP TLV                    January 2025


   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Message version . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  TLV encoding  . . . . . . . . . . . . . . . . . . . . . . . .   3
   5.  BMP Message Format  . . . . . . . . . . . . . . . . . . . . .   5
     5.1.  Common Header . . . . . . . . . . . . . . . . . . . . . .   5
     5.2.  TLV data in Route Monitoring  . . . . . . . . . . . . . .   5
       5.2.1.  Group TLV . . . . . . . . . . . . . . . . . . . . . .   6
       5.2.2.  VRF/Table Name TLV  . . . . . . . . . . . . . . . . .   6
       5.2.3.  Stateless parsing TLV . . . . . . . . . . . . . . . .   6
       5.2.4.  Wire-format example . . . . . . . . . . . . . . . . .   7
     5.3.  TLV data in Peer Down . . . . . . . . . . . . . . . . . .  10
     5.4.  TLV data in other BMP messages  . . . . . . . . . . . . .  10
   6.  Error handling  . . . . . . . . . . . . . . . . . . . . . . .  10
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   8.  Operational Considerations  . . . . . . . . . . . . . . . . .  10
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
   10. Normative References  . . . . . . . . . . . . . . . . . . . .  11
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   The BGP Monitoring Protocol (BMP) version 3 is defined in RFC 7854
   [RFC7854].

   The Route Monitoring message consists of:

   *  Common Header

   *  Per-Peer Header

   *  BGP Update PDU

   The Peer Down Notification message consists of:

   *  Common Header



Lucente & Gu              Expires 21 July 2025                  [Page 2]

Internet-Draft                   BMP TLV                    January 2025


   *  Per-Peer Header

   *  Reason

   *  Data (only if Reason code is 1, 2 or 3)

   *  TLV (only if Reason code is 6)

   This means that both Route Monitoring and Peer Down messages have a
   non-extensible format (except for the specific case of Peer Down
   Reason Code 6 as Section 5.3 of [RFC9069]).  In the Route Monitoring
   case, this prevents the transmission of characteristics of
   transported NLRIs (e.g. to help with stateless parsing), status of a
   path after being processed by the BGP process or of vendor-specific
   data.  In the Peer Down case, this prevents matching with TLVs
   previously sent with the Peer Up message.  The proposal of this
   document is to:

   *  Bump the BMP version for all message types defined in RFC 7854
      [RFC7854] for backward compatibility

   *  Change the structure of Route Monitoring message type so that the
      BGP Update PDU is enclosed in a TLV.  The BGP Message PDU TLV is
      mandatory

   *  Allow all defined BMP message types to make provision for optional
      TLV data.

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 RFC 2119 [RFC2119] RFC 8174 [RFC8174] when, and only when, they
   appear in all capitals, as shown here.

3.  Message version

   For an exporter to flag a receiver that it does comply with this
   document, the Version field of the Common Header, documented in
   Section 4.4 of [RFC7854], MUST be set to 4.  This applies to every
   BMP message type.

4.  TLV encoding

   The TLV data type is already defined in Section 4.4 of [RFC7854] for
   the Initiation and Peer Up message types.  A TLV consists of:




Lucente & Gu              Expires 21 July 2025                  [Page 3]

Internet-Draft                   BMP TLV                    January 2025


   *  2 octets of TLV Type,

   *  2 octets of TLV Length,

   *  0 or more octets of TLV Value.


      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 (2 octets)        |     Length (2 octets)         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      ~                      Value (variable)                         ~
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                                  Figure 1

   TLVs SHOULD be sorted by the sender by their code point.  Multiple
   TLVs of the same type can be repeated as part of the same message,
   and it is left to the specific use-cases whether all, any, the first
   or the last TLV should be considered as well as whether ordering
   matters and repeating is allowed.

   Route Monitoring messages may require per-NLRI TLVs, that is, there
   may be a need to map TLVs to NLRIs contained in the BGP Update
   message, for example, to express additional characteristics of a
   specific NLRI.  For this purpose specifically, TLVs in Route
   Monitoring messages MUST be indexed, with the index starting at one
   (1) to refer to the first NLRI.  Index zero (0) specifies that a TLV
   does apply to all NLRIs contained in the BGP Update message.  The
   Index field is 2 bytes long of which the top-most bit, G-bit, is
   reserved to flag a Group Index (more in Section 5.2.1).  In general
   TLVs of the same type and with the same index can be repeated as part
   of the same message, unless specified otherwise by the definition of
   the specific TLV.  Indexed TLVs are encoded as in the following
   figure:


      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 (2 octets)        |     Length (2 octets)         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |G|      Index (15 bits)        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      ~                      Value (variable)                         ~
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+





Lucente & Gu              Expires 21 July 2025                  [Page 4]

Internet-Draft                   BMP TLV                    January 2025


                                  Figure 2

   Indexed TLVs SHOULD be sorted by the sender by their code point and
   index value.  Also in indexed TLVs, the reported length refers to the
   total encoded TLV value (ie. it does exclude the length of the index
   field).

   A decoder can properly match indexed TLVs to the corresponding NLRI
   only if - or as long as - NLRIs are decoded successfully.  In case of
   any parsing or error condition that prevents full decoding of the BGP
   PDU, the decoder MUST stop matching indexed TLVs to NLRIs.

   Of the BMP message types defined so far, indexed TLVs apply only to
   Route Monitoring messages and, for example, they do not apply to
   Route Mirroring messages because the sender may not be aware of the
   payload of the transported BGP Update message.

5.  BMP Message Format

5.1.  Common Header

   Section 4.1 of [RFC7854] defines the Common Header.  While the
   structure remains unaltered, the following two definitions are
   changed:

   *  Version: Indicates the BMP version.  This is set to '4' for all
      message types defined in RFC 7854 [RFC7854].

   *  Message Length: Total length of the message in bytes (including
      headers, encapsulated BGP Message PDU TLV and optional TLV data).

5.2.  TLV data in Route Monitoring

   The Route Monitoring message type is defined in Section 4.6 of
   [RFC7854].  The consistency model selected by this document to extend
   encoding of such message type with TLVs is with the Route Mirroring
   type defined in Section 4.7 of [RFC7854] where the Per-peer header is
   being followed by mandatory and optional TLVs.

   The BGP Update PDU Section 4.3 of [RFC4271] is encoded itself as part
   of a BGP Message TLV with code point TBD1 and index set to zero.  A
   Route Monitoring message MUST contain one BGP Message TLV which may
   be preceeded and/or followed by other optional TLV data.

   Corollary, in BMPv4 the BGP Update PDU is not just encoded as part of
   the message as it was the case for BMPv3 but it is rather enclosed in
   a TLV.




Lucente & Gu              Expires 21 July 2025                  [Page 5]

Internet-Draft                   BMP TLV                    January 2025


5.2.1.  Group TLV

   In a Route Monitoring message where the BGP Update PDU carries N
   NLRIs, indexed TLVs do allow to handle the cases of 1:1 and N:1
   relationship among TLVs and NLRIs (ie. one TLV applies to one NLRI, N
   TLVs apply to one same NLRI).  The cases of 1:N and M:N relationships
   (ie. one TLV applies to N NLRIs, M TLVs apply to N NLRIs) can benefit
   by a form of grouping.  This is the context to define a Group TLV to
   achieve this with the aim to limit both verbosity and repetitions.

   The TLV value MUST contain:

   *  A 2 bytes Group Index where the top-most bit, G-bit or Group Bit
      MUST be set to one (1).  The full 2 bytes value, that is including
      the G-bit, MUST be unique to the message

   *  Two or more 2 bytes NLRI indexes whose values MUST be less or
      equal to the amount of NLRIs packed in the BGP Update PDU.

   A NLRI index can be listed as part of multiple Group TLVs within the
   same message.  NLRI indexes within a Group TLV SHOULD be sorted by
   the sender.  A Group Index can not reference an NLRI index 0.  A
   Group TLV MUST NOT include its own or another Group Index.  Multiple
   non-Group TLVs can point to the same Group Index, ie. a group can be
   reused within the same Route Monitoring message.

   The Group TLV code point is TBD2.  It is recommended that this TLV is
   encoded first in order to ease parsing of the Route Monitoring
   message at the BMP station side.

5.2.2.  VRF/Table Name TLV

   The Information field contains a UTF-8 string whose value MUST be
   equal to the value of the VRF or table name (ie.  RD instance name)
   being conveyed.  The string size MUST be within the range of 1 to 255
   bytes.

   The VRF/Table Name TLV code point is TBD3

5.2.3.  Stateless parsing TLV

   Stateless parsing helps scaling the amount of Route Monitoring
   messages that can be processed at collection time, avoiding to have
   to correlate them to BGP capabilities received as part of the Peer Up
   message, for example.






Lucente & Gu              Expires 21 July 2025                  [Page 6]

Internet-Draft                   BMP TLV                    January 2025


   Some BGP capabilities are not per AFI/SAFI, like 4-bytes ASN RFC 6793
   [RFC6793], and hence these can be part of the BMP Peer flags section
   of a Route Monitoring message.  Those that are, instead, per AFI/SAFI
   require finer granularity and hence the need to use an indexed TLV.

   The Stateless Parsing TLV code point is TBD4 and is organized as a
   5-bytes registry, one byte for the type, followed by AFI (2 bytes)
   and SAFI (1 byte) and finally one byte for the value.  The type field
   encodes a code point from the Stateless Parsing registry.  The
   following code points are defined for this registry:

   *  Type = TBD5: the BGP Update PDU is encoded with the ADD-PATH
      capability RFC 7911 [RFC7911], the value field MUST be 0 for false
      and 1 for true.

   *  Type = TBD6: the BGP Update PDU is encoded with the Multiple
      Labels capability RFC 8277 [RFC8277], the value field MUST match
      the Count for the relevant AFI/SAFI as it was encoded in the BGP
      Open PDU.

   Only a single Stateless Parsing TLV is allowed in a message, this TLV
   cannot be repeated.  Also the index of the TLV MUST be set to zero.

   If the Stateless Parsing TLV is not present in a Route Monitoring
   message, the receiver MUST fall back to use capabilities present in
   the BGP Open PDU contained in the relevant BMP Peer Up message in
   order to properly parse BGP Update PDUs.

   It is recommended that the Stateless Parsing TLV is encoded
   preceeding the BGP Message TLV in order to ease parsing of the Route
   Monitoring message at the BMP station side.

5.2.4.  Wire-format example

   The diagram in Figure 3 shows an example of a Route Monitoring
   message carrying a BGP UPDATE containing 10 NLRIs.  The TLVs are
   comprised of:

   1.  a Group TLV with index 0x000b, pointing to NLRI 1, 2, 3 and 10

   2.  a Group TLV with index 0x000c, pointing to NLRI 4, 5 and 6

   3.  a Stateless Parsing TLV with Index 0x800b (Group TLV bit set to
       1, Index 0x000b)

   4.  a TLV pertaining to NLRI 7





Lucente & Gu              Expires 21 July 2025                  [Page 7]

Internet-Draft                   BMP TLV                    January 2025


   5.  a TLV pertaining to the NLRIs listed in the Group TLV defined in
       1

   6.  a TLV pertaining to the NLRIs listed in the Group TLV defined in
       2














































Lucente & Gu              Expires 21 July 2025                  [Page 8]

Internet-Draft                   BMP TLV                    January 2025


       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |        Common Header + Per-Peer Header (6 + 48 bytes)         ~
      ~                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            type=TBD2            |         length=0x0008       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |1|           index=0x000b        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  value={0x0001,   0x0002,                     |
      |                         0x0003,   0x000a}                     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            type=TBD2            |         length=0x0006       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |1|           index=0x000c        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  value={0x0004,   0x0005,                     |
      |                         0x0006} |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            type=TBD4            |         length=0x0002       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |1|           index=0x000b        |1|0|                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            type=TBD1            |         length=X            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|           index=0             |    value=$BGP_UPDATE_PDU{   ~
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                             ~
      ~                                                               ~
      ~                       NLRI_1 .. NLRI_10                       ~
      ~                                                            }  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            type=SomeTlvX        |         length=0x0004       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|           index=0x000b        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          value={4 bytes}                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            type=SomeTlvY        |         length=0x0008       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|           index=0x000c        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          value={8 bytes}                      ~
      ~                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                                  Figure 3



Lucente & Gu              Expires 21 July 2025                  [Page 9]

Internet-Draft                   BMP TLV                    January 2025


5.3.  TLV data in Peer Down

   The Peer Down Notification message type is defined in Section 4.9 of
   [RFC7854].  The consistency model selected by this document to extend
   encoding of such message type is with the Peer Up type defined in
   Section 4.10 of [RFC7854] where optional TLVs are placed at the end
   of the message.

   This means for Reason codes 1 or 3, a BGP Notification PDU follows;
   the PDU MAY be further followed by optional TLV data.  For Reason
   code 2, a 2-byte field follows to provide additional FSM info; this
   field MAY be followed by optional TLV data.  For all other Reason
   codes, optional TLV data MAY follow the Reason field.

5.4.  TLV data in other BMP messages

   All other message types defined in RFC7854 [RFC7854] do already
   provision for TLV data.  It is RECOMMENDED that all future defined
   BMP message types will also provide for optional TLV data following a
   consistency model for encoding with existing message types.

6.  Error handling

   It is worth nothing that RFC8654 [RFC8654] permits BGP Update and
   other messages to grow to a length of 65535 octets.  This may cause a
   BMP PDU that attempts to encapsulate such long messages to overflow.

7.  Security Considerations

   It is not believed that this document adds any additional security
   considerations.

8.  Operational Considerations

   In Route Monitoring messages, the number of TLVs can be bound to the
   amount of NLRIs carried in the BGP Update message.  This may degrade
   the packing of information in such messages and have specific impacts
   on the memory and CPU used in a BMP implementation.  As a result of
   that it should always be possible to disable such features to
   mitigate their impact.











Lucente & Gu              Expires 21 July 2025                 [Page 10]

Internet-Draft                   BMP TLV                    January 2025


9.  IANA Considerations

   This document requests the renaming of the "Peer Up TLVs" registry
   defined by BMP Peer Up Message Namespace [I-D.ietf-grow-bmp-peer-up]
   into "Peer Up and Peer Down TLVs" and the definition of one new
   registry "BMP Route Monitoring TLVs".  As part of the "BMP Route
   Monitoring TLVs" registry, the following new TLV types are defined
   (Section 5.2):

   *  Type = TBD1: Support for BGP Message TLV.  The value field is
      defined in Section 5.2

   *  Type = TBD2: Support for grouping of TLVs.  The value field is
      defined in Section 5.2.1.  The recommended value for this TLV is
      0.

   *  Type = TBD3: Support for VRF/Table Name TLV.  The value field is
      defined in Section 5.2.2

   *  Type = TBD4: Support for Stateless Parsing TLV.  The value field
      is defined in Section 5.2.3.  The recommended value for this TLV
      is 1.

   This document also requests the definition of a "Stateless Parsing
   TLV" registry seeded as follows:

   *  Type = TBD5: ADD-PATH capability flag.  Set to 1 if the BGP Update
      PDU enclosed in the Route Monitoring message was encoded according
      to the capability.  The flag is defined in Section 5.2.3.  The
      recommended value for this flag is 0.

   *  Type = TBD6: Multiple Labels capability flag.  The Set to 1 if the
      BGP Update PDU enclosed in the Route Monitoring message was
      encoded according to the capability.  The flag is defined in
      Section 5.2.3.  The recommended value for this flag is 1.

10.  Normative References

   [I-D.ietf-grow-bmp-peer-up]
              Scudder, J. and P. Lucente, "BMP Peer Up Message
              Namespace", Work in Progress, Internet-Draft, draft-ietf-
              grow-bmp-peer-up-05, 2 October 2024,
              <https://datatracker.ietf.org/doc/html/draft-ietf-grow-
              bmp-peer-up-05>.







Lucente & Gu              Expires 21 July 2025                 [Page 11]

Internet-Draft                   BMP TLV                    January 2025


   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
              Border Gateway Protocol 4 (BGP-4)", RFC 4271,
              DOI 10.17487/RFC4271, January 2006,
              <https://www.rfc-editor.org/info/rfc4271>.

   [RFC6793]  Vohra, Q. and E. Chen, "BGP Support for Four-Octet
              Autonomous System (AS) Number Space", RFC 6793,
              DOI 10.17487/RFC6793, December 2012,
              <https://www.rfc-editor.org/info/rfc6793>.

   [RFC7854]  Scudder, J., Ed., Fernando, R., and S. Stuart, "BGP
              Monitoring Protocol (BMP)", RFC 7854,
              DOI 10.17487/RFC7854, June 2016,
              <https://www.rfc-editor.org/info/rfc7854>.

   [RFC7911]  Walton, D., Retana, A., Chen, E., and J. Scudder,
              "Advertisement of Multiple Paths in BGP", RFC 7911,
              DOI 10.17487/RFC7911, July 2016,
              <https://www.rfc-editor.org/info/rfc7911>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8277]  Rosen, E., "Using BGP to Bind MPLS Labels to Address
              Prefixes", RFC 8277, DOI 10.17487/RFC8277, October 2017,
              <https://www.rfc-editor.org/info/rfc8277>.

   [RFC8654]  Bush, R., Patel, K., and D. Ward, "Extended Message
              Support for BGP", RFC 8654, DOI 10.17487/RFC8654, October
              2019, <https://www.rfc-editor.org/info/rfc8654>.

   [RFC9069]  Evens, T., Bayraktar, S., Bhardwaj, M., and P. Lucente,
              "Support for Local RIB in the BGP Monitoring Protocol
              (BMP)", RFC 9069, DOI 10.17487/RFC9069, February 2022,
              <https://www.rfc-editor.org/info/rfc9069>.










Lucente & Gu              Expires 21 July 2025                 [Page 12]

Internet-Draft                   BMP TLV                    January 2025


Acknowledgements

   The authors would like to thank Jeff Haas, Camilo Cardona, Thomas
   Graf, Pierre Francois, Ben Maddison, Tim Evens, Luuk Hendriks,
   Maxence Younsi, Ahmed Elhassany, Colin Petrie, Dhananjay Pakti and
   Shunwan Zhuang for their valuable input.  The authors would also like
   to thank Greg Skinner and Zongpeng Du for their review.

Authors' Addresses

   Paolo Lucente
   NTT
   Veemweg 23
   3771 Barneveld
   Netherlands
   Email: paolo@ntt.net


   Yunan Gu
   Huawei
   Huawei Bld., No.156 Beiqing Rd.
   Beijing
   100095
   China
   Email: guyunan@huawei.com


























Lucente & Gu              Expires 21 July 2025                 [Page 13]