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BMP v4: Extended TLV Support for BGP Monitoring Protocol (BMP)
draft-ietf-grow-bmp-tlv-20

Document Type Active Internet-Draft (grow WG)
Authors Paolo Lucente , Yunan Gu , Maxence Younsi , Pierre Francois
Last updated 2026-03-02
Replaces draft-lucente-bmp-tlv, draft-ietf-grow-bmp-tlv-ebit, draft-younsi-grow-bmp-snts
RFC stream Internet Engineering Task Force (IETF)
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Stream WG state WG Document
Revised I-D Needed - Issue raised by WG
Associated WG milestone
Nov 2025
TLV support for BMP Route Monitoring and Peer Down Messages to IESG
Document shepherd Job Snijders
IESG IESG state I-D Exists
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Send notices to job@fastly.com
draft-ietf-grow-bmp-tlv-20
Global Routing Operations                                     P. Lucente
Internet-Draft                                                       NTT
Updates: 7854 (if approved)                                        Y. Gu
Intended status: Standards Track                                  Huawei
Expires: 3 September 2026                                      M. Younsi
                                                             P. Francois
                                                               INSA-Lyon
                                                            2 March 2026

     BMP v4: Extended TLV Support for BGP Monitoring Protocol (BMP)
                       draft-ietf-grow-bmp-tlv-20

Abstract

   Most of the BGP Monitoring Protocol (BMP) message types make
   provision for data in Type, Length, Value (TLV) format.  However,
   Route Monitoring messages (which provide a snapshot of the monitored
   Routing Information Base) Stats Reports (which supply periodical
   counters) 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 provides consistent and
   extensible structures that would be useful among the various use-
   cases where conveying additional data to a monitoring station is
   required.  This document updates RFC 7854 [RFC7854] to support TLV
   data in all message types and defines some essential TLVs.

   Additionally, this document introduces support for enterprise-
   specific TLVs in the BGP Monitoring Protocol by defining an
   Enterprise Bit (E-bit) that allows usage of per-vendor Type values.

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 3 September 2026.

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Copyright Notice

   Copyright (c) 2026 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 (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  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Message version . . . . . . . . . . . . . . . . . . . . . . .   4
   4.  TLV Encoding  . . . . . . . . . . . . . . . . . . . . . . . .   5
     4.1.  IANA-registered TLV Encoding  . . . . . . . . . . . . . .   5
     4.2.  Enterprise-specific TLV Encoding  . . . . . . . . . . . .   5
     4.3.  IANA-registered Indexed TLV Encoding  . . . . . . . . . .   7
     4.4.  Enterprise-specific Indexed TLV encoding  . . . . . . . .   7
   5.  BMP Message Format  . . . . . . . . . . . . . . . . . . . . .   8
     5.1.  Common Header . . . . . . . . . . . . . . . . . . . . . .   8
     5.2.  TLV Data in Route Monitoring  . . . . . . . . . . . . . .   8
       5.2.1.  Group TLV . . . . . . . . . . . . . . . . . . . . . .   9
       5.2.2.  VRF/Table Name TLV  . . . . . . . . . . . . . . . . .   9
       5.2.3.  Stateless Parsing TLV . . . . . . . . . . . . . . . .   9
     5.3.  TLV Data in Peer Down . . . . . . . . . . . . . . . . . .  10
     5.4.  TLV Data in Stats Reports . . . . . . . . . . . . . . . .  11
     5.5.  TLV Data in Other BMP Messages  . . . . . . . . . . . . .  11
     5.6.  New TLVs in all BMP Messages  . . . . . . . . . . . . . .  11
       5.6.1.  Timestamp TLV . . . . . . . . . . . . . . . . . . . .  11
         5.6.1.1.  Timestamp Types . . . . . . . . . . . . . . . . .  12
       5.6.2.  Sequence Number TLV . . . . . . . . . . . . . . . . .  13
       5.6.3.  Extended Flags TLV  . . . . . . . . . . . . . . . . .  14
   6.  Error Handling  . . . . . . . . . . . . . . . . . . . . . . .  15
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  15
   8.  Operational Considerations  . . . . . . . . . . . . . . . . .  16
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  16
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  18
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  19
     10.2.  Informative References . . . . . . . . . . . . . . . . .  20
   Appendix A.  Wire-format Example  . . . . . . . . . . . . . . . .  20
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  22
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  22

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1.  Introduction

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

   The Route Monitoring message is defined in Section 4.6 of [RFC7854]
   and consists of:

   *  Common Header

   *  Per-Peer Header

   *  BGP Update PDU

   The Stats Reports message is defined in Section 4.8 of [RFC7854] and
   consists of:

   *  Common Header

   *  Per-Peer Header

   *  Stats Count

   *  Stats in TLV format

   The Peer Down Notification message is defined in Section 4.9 of
   [RFC7854] and consists of:

   *  Common Header

   *  Per-Peer Header

   *  Reason

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

   *  TLV (only if Reason code is 6)

   This means that Route Monitoring, Stats Reports and Peer Down
   messages have a non-extensible format (except for the specific case
   of Peer Down Reason Code 6 as specified in Section 5.3 of [RFC9069].
   In the Route Monitoring case, this prevents the transmission of
   parsing characteristics of transported NLRIs (e.g. ADD-PATH, Multi
   Labels, etc.), RIB status of a path (e.g. primary, backup, unused,
   etc.) or of vendor- specific data.  In the Stats Resports and Peer
   Down case, this prevents matching with TLVs previously sent in other
   messages, including the Peer Up message.  This document:

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

   *  Changes 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

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

   Also, vendors need the ability to define proprietary Information
   Elements for reasons such as delivering pre-standard products, this
   need aligns with Section 4.1 of [RFC8126].  The E-bit allows early
   development phases to interoperate among vendors by defining
   enterprise-specific TLVs without conflicting with existing IANA
   allocations.

   The concept of an E-bit is not new.  For example, such mechanism is
   defined in Section 3.2 of [RFC7011] for a very similar purpose.

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.

   The document uses the terms defined in RFC 7854 [RFC7854].

3.  Message version

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

   If a BMP station does not support the version indicated in the
   message, it SHOULD close the session and take the procedures
   described in Error Handling (Section 6)

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4.  TLV Encoding

   The TLV data type (Information TLV) is defined in Section 4.4 of
   [RFC7854] for the Initiation and Peer Up message types.  The
   definition is updated as described in IANA-registered TLV Encoding
   (Section 4.1) and further extended by Enterprise-specific TLV
   Encoding (Section 4.2), IANA-registered Indexed TLV Encoding
   (Section 4.3) and Enterprise-specific Indexed TLV Encoding
   (Section 4.4).

4.1.  IANA-registered TLV Encoding

   *  1 bit to flag an enterprise-specific TLV, set to 0.  The TLV Type
      value must have been defined in IANA-BMP [IANA-BMP]

   *  15 bits of TLV Type,

   *  2 octets of TLV Length, and

   *  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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |E|        Type (15 bits)       |     Length (2 octets)         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      ~                      Value (variable)                         ~
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                                  Figure 1

4.2.  Enterprise-specific TLV Encoding

   Enterprise-specific TLV encoding is defined as follows:

   *  1 bit to flag an enterprise-specific TLV, set to 1

   *  15 bits of TLV Type,

   *  2 octets of TLV length.  Comprising length of IANA PEN plus TLV
      value,

   *  4 octets of IANA Private Enterprise Number IANA-PEN [IANA-PEN]

   *  0 or more octets of TLV Value.

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      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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |E|        Type (15 bits)       |     Length (2 octets)         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                    Enterprise number (4 octets)               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Value (variable)                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                                  Figure 2

   Stats Report messages are also encoded in a TLV-like fashion, as
   documented in Section 4.8 of [RFC7854].  E-bit does hence similarly
   apply to these messages too, with the most relevant bit of Stat Type
   set to 1 in order to flag the presence of a 4-bytes PEN field
   following Stat Len field and preceding Stat Data field, i.e.:

       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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |E|     Stat Type (15 bits)     |     Stat Len (2 octets)       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    Enterprise number (4 octets)               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Stat Data (variable)                   |
       ~                                                               ~
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                                 Figure 3

   While the encoding is not per-se backward compatible, there is no
   existing IANA-allocated Type value that makes use of the most
   significant bit (which is being used in this document to define the
   E-bit), except the experimental and reserved ones mentioned in
   Section 10.5 of [RFC7854], Section 10.6 of [RFC7854] and Section 10.9
   of [RFC7854].  Of these, the Experimental values are being suppressed
   in favor of using the E-bit mechanism described in this document; the
   Reserved value is instead excluded by the E-bit mechanism such that
   no PEN will be included as part of the TLV.

   Future BMP Message Types MUST make use of the TLV encoding defined in
   this document.

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4.3.  IANA-registered Indexed TLV Encoding

   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, TLVs enclosed in a Route Monitoring
   message 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-byte long of which the top-most bit, G-bit, is used to flag a Group
   Index (more in Section 5.2.1).  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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |E|       Type (15 bits)        |     Length (2 octets)         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |G|      Index (15 bits)        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      ~                      Value (variable)                         ~
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                                  Figure 4

   The reported length in indexed TLVs refers to the total encoded TLV
   value (ie. with the length of the index field excluded).

   A monitoring station 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 station MUST stop matching
   indexed TLVs to NLRIs.

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

4.4.  Enterprise-specific Indexed TLV encoding

   For completeness, following is an illustration of the structure of an
   Enterprise-specific Indexed TLV.

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      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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |E|       Type (15 bits)        |     Length (2 octets)         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |G|      Index (15 bits)        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  Enterprise number (4 octets)                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Value (variable)                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                                  Figure 5

5.  BMP Message Format

5.1.  Common Header

   While the structure of the Common header remains unaltered, the
   following two definitions are changed compared to Section 4.1 of
   [RFC7854]:

   *  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

   For consistency with the Route Mirroring type defined in Section 4.7
   of [RFC7854], this document extends the encoding of the Route
   Monitoring message type where the Per-peer header is 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 7 and index set to 0.  A
   Route Monitoring message MUST contain one BGP Message TLV which may
   be preceded or followed by other optional TLV data.

   Corollary, the BGP Update PDU is not encoded as part of the message
   as it was the case for BMPv3 (RFC 7854 [RFC7854]) but it is rather
   enclosed in a TLV.

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5.2.1.  Group TLV

   In a Route Monitoring message where a 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 (i.e., one
   TLV applies to N NLRIs and M TLVs apply to N NLRIs) can benefit by a
   form of grouping.  For that purpose, a Group TLV is defined with the
   aim to limit both verbosity and repetitions.

   The 2-byte index defines a new Group Index and the top-most bit
   (G-bit) MUST be set to 1.  The full 2-byte value, that is including
   the G-bit, MUST be unique to the message

   The value carries two or more 2-byte NLRI indexes whose values MUST
   be less or equal to the amount of NLRIs packed in the BGP Update PDU.

   An 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 MUST NOT reference an NLRI index 0.  A
   Group TLV MUST NOT include its own or another Group Index.  Multiple
   non-Group TLVs MAY point to the same Group Index, i.e., a group can
   be reused within the same Route Monitoring message.

   The Group TLV type is 4.  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 (i.e., RD instance name)
   being conveyed.  The string size MUST be within the range of 1 to 255
   bytes.  This is in line with Section 5.2.1 of [RFC9069].

   The VRF/Table Name TLV type is 5

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.

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

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   use an indexed TLV.  To maintain the consistency between BGP
   Capabilities, they are all carried in Stateless Parsing TLVs,
   regardless of their type.

   The encoding of BGP Capabilities is already generically defined in
   Section 4 of [RFC5492].  It includes every information needed for its
   understanding, including AFI/SAFI codes.  This encoding can be reused
   in the Stateless Parsing TLV, leveraging already existing BGP
   encoders and decoders for implementers.

   The Stateless Parsing TLV type is 6 and its Value is the BGP
   Capability encoded as exactly as it would be in the BGP OPEN of the
   session.  It is thus made of all three Capability Code, Capability
   Length, and Capability Value fields defined in [RFC5492].

   For example, an ADD-PATH capability, as defined by RFC 7911
   [RFC7911], for IP/Unicast with value Send/Receive would be encoded in
   the Capability Value as:

   *  Capability Code, 1 byte, value=69

   *  Capability Length, 1 byte, value=4

   *  AFI, 2 bytes, value=1

   *  SAFI, 1 byte, value=1

   *  Value, 1 byte, value=3

   The index of the Stateless Parsing TLV MUST be set to 0.

   If no Stateless Parsing TLV is 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.  Each BGP capability is to be encoded
   in a separate Stateless Parsing TLV.

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

5.3.  TLV Data in Peer Down

   The Peer Down Notification message type (Section 4.9 of [RFC7854]) is
   extended following a consistent approach with the Peer Up type
   (Section 4.10 of [RFC7854]).  That is, the message is extended so
   that optional TLVs are placed at the end of the message.

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

5.4.  TLV Data in Stats Reports

   The Stats Reports message is extended so that the Stats Count and
   stats data as defined in Section 4.8 of [RFC7854] are all enclosed
   inside a Stats TLV with code- point 1.  The Stats TLV is mandatory
   and can be followed by optional TLV data.

   While the Stats Count field could be used to discriminate among stats
   data and trailing optional TLV data, it is felt that enclosing Stats
   Count and stats data inside a container TLV is cleaner by embracing a
   fully TLV'd body.

5.5.  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.

5.6.  New TLVs in all BMP Messages

   In this section some TLVs are introduced that apply to all existing
   BMP message types and as such will need a code point reserved in all
   TLV registries, namely: BMP Initiation Information TLVs, BMP
   Termination Message TLVs, BMP Route Mirroring TLVs along with
   registries defined in this document BMP Route Monitoring TLVs and BMP
   Peer Up and Peer Down TLVs.  We thus request IANA to allocate, for
   each TLV, the same codepoint value in every TLV codepoint registry of
   this document, as detailed in their respective sections.

5.6.1.  Timestamp TLV

   The Timestamp TLV carries one of multiple types of Timestamp for a
   BMP message.  For each TLV registry seeded in this document, the code
   point of the Timestamp TLV is 3.

   The value of the TLV is the Timestamp Type code, defined in Table 1,
   followed by the timestamp values expressed in seconds and
   microseconds since midnight (zero hour), January 1, 1970 (UTC).

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   The encoding of the timestamp is identical to existing BMP documents
   [RFC7854], [RFC8671], and [RFC9069], except that the timestamp MUST
   NOT be set to zero to indicate unavailability.  The Timestamp TLV is
   optional, a timestamp MUST NOT be included if it is not available.

   The value of the Length field is 9 bytes (1 byte for the Timestamp
   Type field plus the length of the Timestamp fields which are 4 bytes
   each).  The Index field is not included in the length.

   The TLV structure is illustrated in Figure 6.

    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 (2 octets)        |       Length (2 octets)       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |G|      Index (2 octets)       | Timestmp Type |               ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ~              Timestamp (seconds)              |               ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ~            Timestamp (microseconds)           ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                          Figure 6: Timestamp TLV

   The Section 5.6.1.1 defines the list of currently defined Timestamp
   Types.

5.6.1.1.  Timestamp Types

   The Table 1 defines the list of timestamp types that can be carried
   in the Timestamp TLV.  Each timestamp type is described in the
   section associated with its name and code in the table.

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            +======+=====================+===================+
            | Code | Name                | Section           |
            +======+=====================+===================+
            | 0x00 | Trigger Time        | Section 5.6.1.1.1 |
            +------+---------------------+-------------------+
            | 0x01 | Message Export Time | Section 5.6.1.1.2 |
            +------+---------------------+-------------------+
            | 0x02 | Adj-RIB-In Time     | Section 5.6.1.1.3 |
            +------+---------------------+-------------------+
            | 0x03 | Local-RIB Time      | Section 5.6.1.1.4 |
            +------+---------------------+-------------------+
            | 0x04 | Adj-RIB-Out Time    | Section 5.6.1.1.5 |
            +------+---------------------+-------------------+

                                 Table 1

5.6.1.1.1.  Trigger Time

   The Trigger Time is the timestamp of the event which triggered BMP to
   report the event.  This might be a received message, a BGP peering or
   a BMP session going down or up, etc.

5.6.1.1.2.  Message Export Time

   The Message Export Time is the time at which BMP generates the BMP
   message.

5.6.1.1.3.  Adj-RIB-In Time

   The Adj-In Time is the time at which the route has been installed in
   the Adj-RIB-In, as per [RFC7854].

5.6.1.1.4.  Local-RIB Time

   The Local-RIB Time is the time at which the route has been installed
   in the Local-RIB, as per [RFC9069].

5.6.1.1.5.  Adj-RIB-Out Time

   The Adj-Out Time is the time at which the route has been installed in
   the Adj-RIB-Out, as per [RFC8671].

5.6.2.  Sequence Number TLV

   The Sequence Number TLV carries the sequence number of a message in a
   BMP session.  For each TLV registry seeded in this document, the code
   point of the Sequence Number TLV is 1.

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   Ordering of BMP messages based on timestamp becomes complicated when
   timestamps have conflicting meanings or when they are simply
   unavailable.  A Sequence Number on a per BMP session basis allows the
   operator to easily and uniquely identify BMP messages on a BMP
   session.

   The value of the TLV is the sequence number of the BMP message in the
   BMP session, starting at 0, and encoded on 8 bytes.  If the sequence
   number would overflow, the BMP session MUST be reset.

   The value of the Length field is 8.  The Index field is not included
   in the length.

   The TLV structure is illustrated in Figure 7.

    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 (2 octets)        |       Length (2 octets)       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |G|      Index (2 octets)       |                               ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   ~                   Sequence Number (8 octets)                  ~
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   ~                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                       Figure 7: Sequence Number TLV

5.6.3.  Extended Flags TLV

   The Extended Flags TLV carries the Flags field usually present in the
   Per-Peer Header, while extending the length of the field.  This
   allows for a larger range of flags to be allocated in the future.
   For each TLV registry seeded in this document, the code point of the
   Extended Flags TLV is 2.

   The value of the TLV is a sequence of bytes of variable size.  The
   minimum size of the sequence is one, to fit at least the already
   existing flags.  The flags carried in this TLV are defined in the BMP
   Extended Peer Flags IANA registry defined by this document.  The
   first byte of the sequence carries all flags defined previous to this
   document, that is Flags V, L, A, O, and F.  Newly allocated bits will
   be carried in the following byte of the sequence.

   The value of the Length field is the number of bytes in the sequence.
   The Index field is not included in the length.

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   The Index field is set to 0 to indicate the global scope of the TLV.

   The TLV structure is illustrated in Figure 8.

    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 (2 octets)        |       Length (2 octets)       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |G|      Index (2 octets)       |        Flags (Variable)       ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                        Figure 8: Extended Flags TLV

   When this TLV is included in a BMP message, the rightmost bit (X
   Flag) of the Per-Peer Header Flags MUST be set to 1 to indicate that
   the flags to consider are carried in this TLV.  The flags in the Per-
   Peer Header are still set according to the current specification,
   allowing collectors that do not understand the X Flag and Extended
   Flags TLV to still function.

6.  Error Handling

   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.

   A BMP exporter and a BMP station may not support the same version of
   the protocol; being BMP uni-directional, with data flowing only from
   the exporter to the station, the station SHOULD close the BMP session
   and log the condition as a warning; the exporter SHOULD retry to
   connect with a non-aggressitve timer.

   A BMP station may not support some of the TLVs encoded by the
   exporter; the station MUST ignore unsupported TLV types;
   additionally, in case of indexed TLVs, if the index is invalid (i.e.
   out of bounds), the TLV MUST be ignored.  The station SHOULD log the
   condition as a warning.

7.  Security Considerations

   It is not believed that this document adds any additional security
   considerations compared to RFC7854 [RFC7854].

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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.

   TLVs SHOULD be sorted by the sender by their type.  Multiple TLVs of
   the same type can be repeated as part of the same message; 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.

   It is recommended that implementors making use of the Enterprise Bit
   extension have a well-defined internal registry for privately
   assigned code points that is also exposed to the public.

9.  IANA Considerations

   This document requests IANA to rename of the "BMP Peer Up Message
   TLVs" registry defined by BMP Peer Up Message Namespace [RFC9736]
   into "BMP Peer Up and Peer Down TLVs" and the definition of one new
   registry "BMP Route Monitoring TLVs".  The new "BMP Route Monitoring
   TLVs" registry is seeded with the following new TLV types
   (Section 5.2):

   *  Type = 1: Support for Sequence TLV.  The value field is defined in
      Section 5.6.2.

   *  Type = 2: Support for Extended Flags TLV.  The value field is
      defined in Section 5.6.3.

   *  Type = 3: Support for Timestamp TLV.  The value field is defined
      in Section 5.6.1.

   *  Type = 4: Support for grouping of TLVs.  The value field is
      defined in Section 5.2.1.

   *  Type = 5: Support for VRF/Table Name TLV.  The value field is
      defined in Section 5.2.2.

   *  Type = 6: Support for Stateless Parsing TLV.  The value field is
      defined in Section 5.2.3.

   *  Type = 7: Support for BGP Message TLV.  The value field is defined
      in Section 5.2.

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   It is requested the definition of a new "BMP Stats Reports TLVs"
   registry seeded with the following new TLV types (Section 5.4):

   *  Type = 1: Support for Stats TLV to enclose Stats Count and stats
      data.

   *  Type = 1: Support for Sequence TLV.  The value field is defined in
      Section 5.6.2.

   *  Type = 2: Support for Extended Flags TLV.  The value field is
      defined in Section 5.6.3.

   *  Type = 3: Support for Timestamp TLV.  The value field is defined
      in Section 5.6.1.

   Values 0 through 16383 of the "BMP Route Monitoring TLVs" and BMP
   Stats Reports TLVs" registries MUST be assigned using the Standards
   Action policy as defined in Section 4.9 of [RFC8126]; values 16384
   through 32767 MUST be assigned using the First Come First Served
   policy as defined in Section 4.4 of [RFC8126].  The upper bound of
   the registry is 65535.  Value 65535 is Reserved.

   The TLV Type values used by BMP are managed by IANA as are the
   Private Enterprise Numbers used by enterprise-specific Type values
   IANA-PEN [IANA-PEN].

   For BMP Initiation Information TLVs, BMP Termination Message TLVs,
   BMP Peer Up and Peer Down TLVs and BMP Route Mirroring TLVs
   registries it is requested to make the range 0-16383 as Standards
   Action (down from current 0-32767); it also asks to make the range
   16384-32767 as First Come First Served (in place of current
   32768-65530).

   This document also requests to remove the Experimental allocation
   from the same registries, the code points now flagged Experimental
   will become Unassigned.  The top most bit of each registry will be
   reserved to the E-bit, reducing the Unassigned pool: the maximum
   availble value for assignment for the registries will be 32767 (ie.
   as opposed to current 65530).

   Finally, for the same registries, this document requests IANA to
   allocate the codepoints for Timestamp TLV (TBD1), Sequence Number TLV
   (TBD2) and Extended Flags TLV (TBD3).  It is recommended that the
   code points are assigned consistently to the registry seeded in this
   document (ie.  Timestamp TLV = 3 , etc.).

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   This document requests that IANA assigns the following new parameters
   to the BMP Peer Flags for Peer Types 0 through 2; registry and to the
   BMP Peer Flags for Loc-RIB Instance Peer Type registry:

   * Flag = 7: X Flag (Extended Flags).  Set if the Flags are carried in
   the Extended Flags TLV instead of the Per-Peer Header.

   This document also requests the definition of a BMP Extended Peer
   Flags; registry which contains flags contained in the Extended Flags
   TLV The size of this registry is TBD.  The registration policy for
   this registry is Standards Action as defined in [RFC8126].

   The registry is seeded as follows:

   *  Flag 0: V flag [RFC7854]
   *  Flag 1: L flag [RFC7854]
   *  Flag 2: A flag [RFC7854]
   *  Flag 3: O flag [RFC8671]
   *  Flag 4: F flag [RFC9069]

   This document also requests the definition of a BMP Timestamp Types
   registry.  This registry contains type codes for the kinds of
   timestamps carried by the Timestamp TLV.  The size of the registry
   matches the size of the Timestamp Type field defined in Figure 6
   which is 1 byte.

   The registration policy for this registry is Expert Review as defined
   in [RFC8126].

   The registry is seeded as follows:

   *  Type = 0x00: Trigger Time.  Set to 0x00 if the timestamp
      corresponds to the event that triggered BMP to report the route or
      state, such as receiving a message or a session transition.
   *  Type = 0x01: Message Export Time.  Set to 0x01 if the timestamp
      corresponds to the time when the BMP message was generated for
      export.
   *  Type = 0x02: Adj-In Time.  Set to 0x02 if the timestamp
      corresponds to when the route was installed in the Adj-RIB-In, as
      per [RFC7854].
   *  Type = 0x03: Local-RIB Time.  Set to 0x03 if the timestamp
      corresponds to when the route was installed in the Local-RIB, as
      per [RFC9069].
   *  Type = 0x04: Adj-Out Time.  Set to 0x04 if the timestamp
      corresponds to when the route was installed in the Adj-RIB-Out, as
      per [RFC8671].

10.  References

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10.1.  Normative References

   [I-D.boucadair-nmop-rfc3535-20years-later]
              Boucadair, M., Contreras, L. M., de Dios, O. G., Graf, T.,
              Rahman, R., and L. Tailhardat, "RFC 3535, 20 Years Later:
              An Update of Operators Requirements on Network Management
              Protocols and Modelling", Work in Progress, Internet-
              Draft, draft-boucadair-nmop-rfc3535-20years-later-08, 12
              May 2025, <https://datatracker.ietf.org/doc/html/draft-
              boucadair-nmop-rfc3535-20years-later-08>.

   [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>.

   [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>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/info/rfc8126>.

   [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>.

   [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>.

   [RFC8671]  Evens, T., Bayraktar, S., Lucente, P., Mi, P., and S.
              Zhuang, "Support for Adj-RIB-Out in the BGP Monitoring
              Protocol (BMP)", RFC 8671, DOI 10.17487/RFC8671, November
              2019, <https://www.rfc-editor.org/info/rfc8671>.

   [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>.

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   [RFC9736]  Scudder, J. and P. Lucente, "The BGP Monitoring Protocol
              (BMP) Peer Up Message Namespace", RFC 9736,
              DOI 10.17487/RFC9736, March 2025,
              <https://www.rfc-editor.org/info/rfc9736>.

10.2.  Informative References

   [IANA-BMP] IANA, "BGP Monitoring Protocol (BMP) Parameters", 2016,
              <https://www.iana.org/assignments/bmp-parameters/bmp-
              parameters.xhtml>.

   [IANA-BPPF]
              IANA, "BMP Peer Flags", 2024,
              <https://www.iana.org/assignments/bmp-parameters/bmp-
              parameters.xhtml#peer-flags>.

   [IANA-PEN] IANA, "Private Enterprise Numbers", 1982,
              <http://www.iana.org/assignments/enterprise-numbers/>.

   [RFC5492]  Scudder, J. and R. Chandra, "Capabilities Advertisement
              with BGP-4", RFC 5492, DOI 10.17487/RFC5492, February
              2009, <https://www.rfc-editor.org/info/rfc5492>.

   [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>.

   [RFC7011]  Claise, B., Ed., Trammell, B., Ed., and P. Aitken,
              "Specification of the IP Flow Information Export (IPFIX)
              Protocol for the Exchange of Flow Information", STD 77,
              RFC 7011, DOI 10.17487/RFC7011, September 2013,
              <https://www.rfc-editor.org/info/rfc7011>.

   [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>.

Appendix A.  Wire-format Example

   The diagram in Figure 9 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

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   3.  a Stateless Parsing TLV with index 0x0000, stating that the Add-
       Path Capability is set to Both (Snd/Rcv) for the IPv4 Unicast
       address family in the BGP UPDATE.

   4.  a TLV pertaining to NLRI 7

   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

      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 + 42 bytes)         ~
      ~                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|          type=2             |         length=0x0008         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |1|           index=0x0001      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  value={0x0001,   0x0002,                     |
      |                         0x0003,   0x000a}                     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|          type=2             |        length=0x0006          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |1|           index=0x0002      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  value={0x0004,   0x0005,                     |
      |                         0x0006}                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|          type=4             |         length=0x0005         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|           index=0           |     code=69   |     len=4     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |      afi=1    |    safi=1     |     value=3   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|          type=1             |         length=X              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|           index=0           |    value=$BGP_UPDATE_PDU{     ~
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               ~
      ~                                                               ~
      ~                       NLRI_1 .. NLRI_10                       ~
      ~                                                            }  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|          type=SomeTlvX      |         length=0x0004         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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      |1|           index=0x0001      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          value={4 bytes}                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|          type=SomeTlvY      |         length=0x0008         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |1|           index=0x0002      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          value={8 bytes}                      ~
      ~                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|          type=SomeTlvZ      |         length=0x0008         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |0|           index=0x0007      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          value={8 bytes}                      ~
      ~                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                                  Figure 9

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, Zongpeng Du and Mohamed Boucadair 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

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   Maxence Younsi
   INSA-Lyon
   France
   Email: maxence.younsi@insa-lyon.fr

   Pierre Francois
   INSA-Lyon
   France
   Email: pierre.francois@insa-lyon.fr

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