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MPLS Data Plane Encapsulation for In-situ OAM Data
draft-gandhi-mpls-ioam-06

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This is an older version of an Internet-Draft whose latest revision state is "Active".
Authors Rakesh Gandhi , Zafar Ali , Frank Brockners , Bin Wen , Bruno Decraene , Haoyu Song , Voitek Kozak
Last updated 2022-10-03
Replaces draft-gandhi-mpls-ioam-sr
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draft-gandhi-mpls-ioam-06
MPLS Working Group                                        R. Gandhi, Ed.
Internet-Draft                                                    Z. Ali
Intended status: Standards Track                            F. Brockners
Expires: 6 April 2023                                Cisco Systems, Inc.
                                                                  B. Wen
                                                                 Comcast
                                                             B. Decraene
                                                                  Orange
                                                                 H. Song
                                                  Futurewei Technologies
                                                                V. Kozak
                                                                 Comcast
                                                          3 October 2022

           MPLS Data Plane Encapsulation for In-situ OAM Data
                       draft-gandhi-mpls-ioam-06

Abstract

   In-situ Operations, Administration, and Maintenance (IOAM) is used
   for recording and collecting operational and telemetry information
   while the packet traverses a path between two points in the network.
   This document defines how IOAM data fields are transported with MPLS
   data plane encapsulation using MPLS Network Action (MNA).

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
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   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 6 April 2023.

Copyright Notice

   Copyright (c) 2022 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   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.  Conventions . . . . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Requirement Language  . . . . . . . . . . . . . . . . . .   3
     2.2.  Abbreviations . . . . . . . . . . . . . . . . . . . . . .   3
   3.  MPLS Extensions for IOAM Data Fields  . . . . . . . . . . . .   4
     3.1.  IOAM Extension Header . . . . . . . . . . . . . . . . . .   4
     3.2.  Post-Stack Network Action Presence Indicators . . . . . .   6
   4.  Edge-to-Edge IOAM Network Action  . . . . . . . . . . . . . .   6
     4.1.  Post-Stack Network Action Presence Indicator  . . . . . .   7
     4.2.  Procedure for Edge-to-Edge IOAM Network Action  . . . . .   7
   5.  Hop-By-Hop IOAM Network Action  . . . . . . . . . . . . . . .   8
     5.1.  Hop-By-Hop Post-Stack Network Action Processing
           Indicator . . . . . . . . . . . . . . . . . . . . . . . .   8
     5.2.  Procedure for Hop-By-Hop IOAM Network Action  . . . . . .   9
     5.3.  Hop-By-Hop and Edge-To-Edge IOAM Extension Headers  . . .   9
   6.  Considerations for IOAM . . . . . . . . . . . . . . . . . . .  10
     6.1.  Considerations for ECMP . . . . . . . . . . . . . . . . .  10
     6.2.  Node Capability . . . . . . . . . . . . . . . . . . . . .  10
     6.3.  Nested MPLS Encapsulation . . . . . . . . . . . . . . . .  10
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  11
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  12
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  12

1.  Introduction

   In-situ Operations, Administration, and Maintenance (IOAM) is used
   for recording and collecting operational and telemetry information
   while the packet traverses a path between two points in the network.
   The term "in-situ" refers to the fact that the IOAM data fields are
   added to the data packets rather than being sent within the probe
   packets specifically dedicated to OAM.  The IOAM data fields are
   defined in [RFC9197].  The IOAM data fields are further updated in
   [I-D.ietf-ippm-ioam-direct-export] for direct export use-cases.

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   This document defines how IOAM data fields are transported with MPLS
   data plane encapsulations using MPLS Network Action (MNA)
   [I-D.ietf-mpls-mna-fwk].

   Note: This document uses MNA encoding defined in Individual Internet
   Drafts as examples.  The MNA encoding will be updated to align with
   the MNA solutions in the WG adopted Internet Drafts.

2.  Conventions

2.1.  Requirement Language

   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] [RFC8174]
   when, and only when, they appear in all capitals, as shown here.

2.2.  Abbreviations

   The MPLS Network Action (MNA) terminology defined in
   [I-D.ietf-mpls-mna-fwk] are used in this document.

   Abbreviations used in this document:

   PNI  Post-Stack Network Action Presence Indicator

   ECMP  Equal Cost Multi-Path

   E2E  Edge-To-Edge

   HBH  Hop-By-Hop

   HPI  Hop-By-Hop Post-Stack Network Action Processing Indicator

   IOAM  In-situ Operations, Administration, and Maintenance

   MPLS  Multiprotocol Label Switching

   MNA  MPLS Network Action

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   OAM  Operations, Administration, and Maintenance

   POT  Proof-of-Transit

3.  MPLS Extensions for IOAM Data Fields

3.1.  IOAM Extension Header

   The IOAM extension headers containing different IOAM-Data-Fields are
   added in the MPLS packet as shown in Figure 1.  The IOAM-Data-Fields
   MUST follow the definitions corresponding to the IOAM-Option-Types
   (e.g., see Section 4.4 of [RFC9197] and Section 3 of
   [I-D.ietf-ippm-ioam-direct-export]).

   An IOAM extension header uses Extension Header (EH) defined in
   [I-D.song-mpls-extension-header].

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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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |1ST-NIB| EH-CN | EH-TOTAL-LEN  |ORG-UL-PROTOCOL|NEXT-HDR = IOAM| CH
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |NEXT-HDR = IOAM| IOAM-HDR-LEN  |R|IOAM-OPT-TYPE| BLOCK-NUMBER  | EH
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |                                                               |  I
   |                                                               |  O
   ~               IOAM Option and Data Space [RFC9197]            ~  A
   |                     [draft-ietf-ippm-ioam-direct-export]      |  M
   |                                                               |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   .                                                               .
   .                                                               .
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   | NEXT-HDR      | IOAM-HDR-LEN  |R|IOAM-OPT-TYPE| BLOCK-NUMBER  | EH
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |                                                               |  I
   |                                                               |  O
   ~               IOAM Option and Data Space [RFC9197]            ~  A
   |                     [draft-ietf-ippm-ioam-direct-export]      |  M
   |                                                               |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |                                                               |
   |                                                               |
   ~               Optional Payload + Padding                      ~
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             Figure 1: Extension Headers with IOAM Data Fields

   The 4-Octet Common Header CH) is added with the following fields in
   the MPLS header as defined in [I-D.song-mpls-extension-header]:

   1ST-NIBBLE (R):  The first 4-bit is Reserved (value TBA4).

   EH-CN (EHC):  The EH Count, number of EHs carried in the packet.

   EH-TOTAL-LEN (EHTL):  Total Length of EHs in the packet in 4-octet
     units.

   ORIG-UL-PROTOCOL (OUL):  The Original Upper Layer Protocol.

   NEXT-HDR (NH):  The Next Header protocol.  For IOAM as Next Header,
     value TBA2 is to be assigned by IANA.

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   IOAM-Data-Fields are added in EHs containing the following fields:

   IOAM-OPT-TYPE:  8-bit field defining the IOAM Option type, as defined
     in the "IOAM Option-Type Registry" specified in [RFC9197] and
     [I-D.ietf-ippm-ioam-direct-export]).

   IOAM-HDR-LEN:  8-bit unsigned integer.  Length of the IOAM Header in
     4-octet units.

   IOAM Option and Data Space:  IOAM-Data-Fields as specified by the
     IOAM-OPT-Type field.  IOAM-Data-Fields are defined corresponding to
     the IOAM-Option-Type (e.g., see Section 4.4 of [RFC9197] and
     Section 3 of [I-D.ietf-ippm-ioam-direct-export].

   BLOCK-NUMBER:  The Block Number can be used to aggregate the IOAM
     data collected in data plane, e.g., to compute measurement metrics
     for each block of a data flow.  It is also used to correlate the
     IOAM data on different nodes.

3.2.  Post-Stack Network Action Presence Indicators

   A Post-Stack Network Action Presence Indicator MUST be added to
   indicate the presence of the IOAM-Data-Fields in the MPLS header.  If
   both edge and intermediate nodes need to process IOAM data then both
   the Post-Stack Network Action Presence Indicator and the HBH Network
   Action Processing Indicator MUST be added.  The HBH Network Action
   Processing Indicator allows to optimize the IOAM processing on the
   intermediate nodes and avoids the need to parse all IOAM-Data-Fields.

   A flag called PNI (Post-Stack Network Action Presence Indicator) in
   the TTL field defined in [I-D.jags-mpls-mna-hdr] is used in this
   document to indicate the presence of IOAM Post-Stack Network Action
   and Ancillary Data.

   A flag called HPI (Hop-By-Hop Post-Stack Network Action Processing
   Indicator) in the TTL field defined in [I-D.jags-mpls-mna-hdr] is
   used to indicate that HBH processing is required for the Post-Stack
   Network Action and the associated Ancillary Data.

   The MNA Label used in this document is a Base Special Purpose Label
   (bSPL value TBA1 to be assigned by IANA), and is defined as Network
   Action Sub-Stack Indicator (NASI) in [I-D.jags-mpls-mna-hdr].

4.  Edge-to-Edge IOAM Network Action

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4.1.  Post-Stack Network Action Presence Indicator

   The Post-Stack Network Action Presence Indicator is set to "1" to
   indicate the presence of the IOAM-Data-Fields in the MPLS header as
   shown in Figure 2.

    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
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |  Label                                | TC  |S|  TTL          |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    .                                                               .
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |  MNA Label (bSPL value TBA1)          | TC  |S|  TTL          |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                                       | TC  |S| PNI=1, HPI=0  |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    .                                                               .
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                Packet as shown in Figure 1                    |
    .                                                               .
    +---------------------------------------------------------------+

             Figure 2: Example MPLS Encapsulation for E2E IOAM

   The E2E IOAM-Data-Fields carry the Option-Type(s) that require
   processing on the encapsulating and decapsulating nodes only.  The
   IOAM Option-Type carried can be IOAM Edge-to-Edge Option-Type (value
   3) [RFC9197] as well as Direct Export (DEX) Option-Type (value 4, to
   be assigned by IANA) defined in [I-D.ietf-ippm-ioam-direct-export].
   The E2E IOAM-Data-Fields SHOULD NOT carry any IOAM Option-Type that
   require IOAM processing on the intermediate nodes as it will not be
   processed by them since HPI flag is not set.

4.2.  Procedure for Edge-to-Edge IOAM Network Action

   The E2E IOM Network Action procedure is summarized as following:

   *  The encapsulating node inserts the MNA Label (bSPL value TBA1)
      with the Post-Stack Network Action Presence Indicator (TTL Flag
      PNI) set to "1" below the label whose FEC is the decapsulating
      node and one or more IOAM-Data-Fields in the MPLS packet.

   *  The intermediate nodes do not process IOAM-Data-Fields.

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   *  The penultimate node MUST NOT remove the MNA Sub-stack from the
      MPLS header so that the MNA Sub-stack is received at the
      decapsulating node.  This encapsulating node adds required MPLS
      header so that the received packet on the penultimate node does
      not have MNA Sub-stack at the top of the Label stack.

   *  The decapsulating node MAY punt a copy of the packet with the
      receive timestamp to the slow path for IOAM-Data-Fields processing
      when the node recognizes the PNI is set to "1".  The receive
      timestamp is required by the various E2E OAM use-cases, including
      streaming telemetry.  Note that the packet is not necessarily
      punted to the control-plane.

   *  The decapsulating node processes the IOAM-Data-Fields using the
      procedures defined in [RFC9197].  An example of IOAM processing is
      to export the IOAM-Data-Fields, send IOAM-Data-Fields via
      streaming telemetry, etc.

   *  The decapsulating node MUST remove the IOAM-Data-Fields from the
      received packet.  The decapsulated packet is forwarded downstream
      or terminated locally similar to the regular IOAM-Data-Fields.

5.  Hop-By-Hop IOAM Network Action

5.1.  Hop-By-Hop Post-Stack Network Action Processing Indicator

   The Post-Stack Network Action Presence Indicator (TTL Flag PNI) along
   with Hop-By-Hop Processing Indicator (TTL Flag HPI) are set to "1" to
   indicate the presence of the HBH IOAM-Data-Fields in the MPLS header
   as shown in Figure 3.

    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
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |  Label                                | TC  |S|  TTL          |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    .                                                               .
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |  MNA Label (bSPL value TBA1)          | TC  |S|  TTL          |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                                       | TC  |S| PNI=1, HPI=1  |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    .                                                               .
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                Packet as shown in Figure 1                    |
    .                                                               .
    +---------------------------------------------------------------+

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             Figure 3: Example MPLS Encapsulation for HBH IOAM

   The HBH IOAM-Data-Fields carry the Option-Type(s) that require
   processing at the intermediate and/or encapsulating and decapsulating
   nodes.  The IOAM Option-Type carried can be IOAM Pre-allocated Trace
   Option-Type (value 0), IOAM Incremental Trace Option-Type (value 1)
   and IOAM Proof of Transit (POT) Option-Type (value 2), and Edge-to-
   Edge Option-Type (value 3) defined in [RFC9197] as well as Direct
   Export (DEX) Option-Type (value 4, to be assigned by IANA) defined in
   [I-D.ietf-ippm-ioam-direct-export].

5.2.  Procedure for Hop-By-Hop IOAM Network Action

   The Hop-By-Hop IOAM Network Action procedure is summarized as
   following:

   *  The encapsulating node inserts the MNA Label (bSPL value TBA1)
      with the Post-Stack Network Action Presence Indicator (TTL Flag
      PNI) and HBH Processing Indicator (TTL Flag HPI) set to "1" below
      the label whose FEC is the decapsulating node and one or more
      IOAM-Data-Fields in the MPLS packet.

   *  The intermediate node enabled with HBH IOAM function processes the
      data packet including the IOAM-Data-Fields as defined in [RFC9197]
      and [I-D.ietf-ippm-ioam-direct-export] when the node recognizes
      the HBH Processing Indicator in the MPLS header.

   *  The intermediate node MAY punt a copy of the packet with the
      receive timestamp to the slow path for IOAM-Data-Fields processing
      when the node recognizes the HBH Processing Indicator.  The
      receive timestamp is required by the various HBH OAM use-cases,
      including streaming telemetry.  Note that the packet is not
      necessarily punted to the control-plane.

   *  The intermediate node forwards a copy of the processed data packet
      downstream.

   *  The behavior on the penultimate node is same as E2E case.

   *  The processing on the decapsulating node is same as E2E case.

5.3.  Hop-By-Hop and Edge-To-Edge IOAM Extension Headers

   Both HBH and E2E IOAM EHs may be added in an MPLS header.  In this
   case the HBH IOAM EHs MUST be added after the BOS and before the E2E
   IOAM EHs.  When an intermediate node encounters the first E2E IOAM
   EH, it will stop processing of the E2E EH.

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6.  Considerations for IOAM

6.1.  Considerations for ECMP

   The encapsulating node needs to make sure the IOAM-Data-Fields do not
   start with a well-known IP Version Number (e.g. 0x4 for IPv4 and 0x6
   for IPv6) as that can alter the hashing function for ECMP that uses
   the IP header.  This is achieved by using the Common Header (CH) with
   a different IP Version Number (value TBA4) after the MPLS label
   stack.

6.2.  Node Capability

   The decapsulating node that has to remove the IOAM-Data-Fields and
   perform the IOAM function may not be capable of supporting it.  The
   encapsulating node needs to know if the decapsulating node can
   support the IOAM function.  The signaling extension for this
   capability exchange is outside the scope of this document.

   The intermediate node that is not capable of supporting the IOAM
   functions defined in this document, can simply skip the IOAM
   processing.

   The node that does not recognize the MNA Label received at the top of
   the label stack will drop the packet.

6.3.  Nested MPLS Encapsulation

   When a packet is received with MPLS Encapsulated IOAM Network Action,
   the nested MPLS encapsulating node that supports a different IOAM
   Network Action, the node MUST add a new MNA Label (with Sub-Stack)
   with the supported IOAM Network Action as part of the new MPLS
   encapsulation.

7.  Security Considerations

   The security considerations of IOAM in general are discussed in
   [RFC9197] and apply to the procedure defined in this document.

   IOAM is considered a "per domain" feature, where one or several
   operators decide on configuring IOAM according to their needs.  IOAM
   is intended for deployment in limited domains [RFC8799].  As such, it
   assumes that a node involved in IOAM operation has previously
   verified the integrity of the path.  Still, operators need to
   properly secure the IOAM domain to avoid malicious configuration and
   use, which could include injecting malicious IOAM packets into the
   domain.

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8.  IANA Considerations

   The encoding of Next-Header uses the same value registry for IPv4/
   IPv6 protocol numbers.  The value TBA2 for IOAM as Next Header shall
   be assigned by IANA from the "Protocol Numbers" registry
   (https://www.iana.org/assignments/protocol-numbers/protocol-
   numbers.xhtml).

9.  References

9.1.  Normative References

   [I-D.ietf-ippm-ioam-direct-export]
              Song, H., Gafni, B., Brockners, F., Bhandari, S., and T.
              Mizrahi, "In-situ OAM Direct Exporting", Work in Progress,
              Internet-Draft, draft-ietf-ippm-ioam-direct-export-11, 23
              September 2022, <https://www.ietf.org/archive/id/draft-
              ietf-ippm-ioam-direct-export-11.txt>.

   [I-D.jags-mpls-mna-hdr]
              Rajamanickam, J., Gandhi, R., Bhattacharya, J., Decraene,
              B., Zigler, R., Cheng, W., Jalil, L., and H. Song, "MPLS
              Network Action Header Encodings", Work in Progress,
              Internet-Draft, draft-jags-mpls-mna-hdr-01, 25 July 2022,
              <https://www.ietf.org/archive/id/draft-jags-mpls-mna-hdr-
              01.txt>.

   [I-D.song-mpls-extension-header]
              Song, H., Li, Z., Zhou, T., Andersson, L., Zhang, Z.,
              Gandhi, R., Rajamanickam, J., and J. Bhattacharya, "MPLS
              Extension Header", Work in Progress, Internet-Draft,
              draft-song-mpls-extension-header-10, 10 September 2022,
              <https://www.ietf.org/archive/id/draft-song-mpls-
              extension-header-10.txt>.

   [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>.

   [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>.

   [RFC9197]  Brockners, F., Bhandari, S., and T. Mizrahi, "Data Fields
              for In Situ Operations, Administration, and Maintenance",
              RFC 9197, May 2022,
              <https://www.rfc-editor.org/info/rfc9197>.

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9.2.  Informative References

   [I-D.ietf-mpls-mna-fwk]
              Andersson, L., Bryant, S., Bocci, M., and T. Li, "MPLS
              Network Actions Framework", Work in Progress, Internet-
              Draft, draft-ietf-mpls-mna-fwk-01.txt, 8 September 2022,
              <https://www.ietf.org/archive/id/draft-ietf-mpls-mna-fwk-
              01.txt>.

   [RFC8799]  Carpenter, B. and B. Liu, "Limited Domains and Internet
              Protocols", RFC 8799, DOI 10.17487/RFC8799, July 2020,
              <https://www.rfc-editor.org/info/rfc8799>.

Acknowledgements

   The authors would like to thank Patrick Khordoc, Sagar Soni, Shwetha
   Bhandari, Clarence Filsfils, and Vengada Prasad Govindan for the
   discussions on IOAM.  The authors would also like to thank Tarek
   Saad, Loa Andersson, Greg Mirsky, Stewart Bryant, Xiao Min, and Cheng
   Li for providing many useful comments.  The authors would also like
   to thank Mach Chen, Andrew Malis, Matthew Bocci, and Nick Delregno
   for the MPLS-RT reviews.

Authors' Addresses

   Rakesh Gandhi (editor)
   Cisco Systems, Inc.
   Canada
   Email: rgandhi@cisco.com

   Zafar Ali
   Cisco Systems, Inc.
   Email: zali@cisco.com

   Frank Brockners
   Cisco Systems, Inc.
   Hansaallee 249, 3rd Floor
   DUESSELDORF, NORDRHEIN-WESTFALEN 40549
   Germany
   Email: fbrockne@cisco.com

   Bin Wen
   Comcast
   Email: Bin_Wen@cable.comcast.com

Gandhi, et al.            Expires 6 April 2023                 [Page 12]
Internet-Draft       In-situ OAM for MPLS Data plane        October 2022

   Bruno Decraene
   Orange
   Email: bruno.decraene@orange.com

   Haoyu Song
   Futurewei Technologies
   United States of America
   Email: haoyu.song@futurewei.com

   Voitek Kozak
   Comcast
   Email: Voitek_Kozak@comcast.com

Gandhi, et al.            Expires 6 April 2023                 [Page 13]