



IPPM Working Group                                        R. Gandhi, Ed.
Internet-Draft                                       Cisco Systems, Inc.
Intended status: Standards Track                                 T. Zhou
Expires: 5 December 2026                                          Huawei
                                                                   Z. Li
                                                            China Mobile
                                                                 F. Ihle
                                                 University of Tuebingen
                                                             3 June 2026


   Simple Two-Way Active Measurement Protocol (STAMP) Extensions for
             Reflecting STAMP Packet MPLS Extension Headers
                  draft-gandhi-ippm-stamp-mpls-hdr-04

Abstract

   The Simple Two-Way Active Measurement Protocol (STAMP) and its
   optional extensions can be used for Edge-to-Edge (E2E) active
   measurement.  In Situ Operations, Administration, and Maintenance
   (IOAM) data fields can be used for recording and collecting Hop-by-
   Hop (HBH) and E2E operational and telemetry information.  This
   document extends STAMP to reflect MPLS extension headers, including
   MPLS Network Action Sub-Stacks and Post-Stack Header, for HBH and E2E
   active measurements, for example, using IOAM data fields.

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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   This Internet-Draft will expire on 5 December 2026.

Copyright Notice

   Copyright (c) 2026 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 Used in This Document . . . . . . . . . . . . . .   3
     2.1.  Requirements Language . . . . . . . . . . . . . . . . . .   3
     2.2.  Abbreviations . . . . . . . . . . . . . . . . . . . . . .   3
     2.3.  STAMP Reference Topology  . . . . . . . . . . . . . . . .   4
   3.  Overview  . . . . . . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  One-Way and Two-Way Measurement Types . . . . . . . . . .   8
     3.2.  Receiving MPLS Header from the Data Plane on Egress
           Node  . . . . . . . . . . . . . . . . . . . . . . . . . .   8
   4.  Use Case of Reflecting IOAM Data Fields . . . . . . . . . . .   9
   5.  STAMP Extensions  . . . . . . . . . . . . . . . . . . . . . .  10
     5.1.  Reflected MPLS Header MNA Data TLV  . . . . . . . . . . .  10
     5.2.  MNA Header Control Sub-TLV  . . . . . . . . . . . . . . .  10
   6.  Operational Considerations  . . . . . . . . . . . . . . . . .  11
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  11
   8.  Implementation Status . . . . . . . . . . . . . . . . . . . .  11
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  12
     10.2.  Informative References . . . . . . . . . . . . . . . . .  13
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   The Simple Two-Way Active Measurement Protocol (STAMP) provides
   capabilities for the measurement of various performance metrics in IP
   networks [RFC8762] without the use of a control channel to pre-signal
   session parameters.  [RFC8972] defines optional extensions in the
   form of TLVs for STAMP.  The STAMP test packets are transmitted along
   a path between a Session-Sender and a Session-Reflector to measure
   Edge-to-Edge (E2E) performance delay and packet loss along that path.

   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 IOAM data fields are defined in [RFC9197].  Currently, there is



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   no adopted method defined to reflect the collected IOAM data fields
   back to the Sender, where the Sender can use that information to
   support the hop-by-hop and edge-to-edge measurement use cases.

   MPLS packets may carry MPLS Network Action (MNA) Sub-Stacks as
   defined in [I-D.ietf-mpls-mna-hdr] and Post-Stack Header (PSH) as
   defined in [I-D.ietf-mpls-mna-ps-hdr].

   It may be desired to record and collect HBH and E2E operational and
   telemetry information using active measurement packets between two
   nodes in a network.  This is achieved by augmenting STAMP [RFC8762],
   using optional STAMP extensions defined in [RFC8972], to reflect MPLS
   extension headers, including Network Action Sub-Stacks (NASes) and
   PSH, as specified in this document.  The procedure defined in this
   document leverages the existing implementations on the midpoint nodes
   with an MPLS data plane that support the NAS and PSH used, without
   any additional requirements.

2.  Conventions Used in This Document

2.1.  Requirements Language

   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 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

2.2.  Abbreviations

   ECMP: Equal Cost Multi-Path

   E2E: Edge-to-Edge

   HBH: Hop-by-Hop

   IOAM: In Situ Operations, Administration, and Maintenance

   MNA: Multiprotocol Label Switching Network Action

   MTU: Maximum Transmission Unit

   NAS: Network Action Sub-Stack

   PSH: Post-Stack Header

   STAMP: Simple Two-Way Active Measurement Protocol




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   TLV: Type-Length-Value

2.3.  STAMP Reference Topology

   In the "STAMP Reference Topology" shown in Figure 1, the STAMP
   Session-Sender S1 initiates a Session-Sender test packet, and the
   STAMP Session-Reflector R1 transmits a reply Session-Reflector test
   packet.  Node M1 is a midpoint node that performs an MPLS network
   action but does not perform any STAMP protocol processing.

   T1 is a transmit timestamp, and T4 is a receive timestamp added by
   node S1 in a STAMP test packet payload.  T2 is a receive timestamp,
   and T3 is a transmit timestamp added by node R1 in a STAMP test
   packet payload.

              T1                                       T2
             /                                           \
    +-------+    Test Packet  +-------+                   +-------+
    |       | - - - - - - - - |       | - - - - - - - - ->|       |
    |   S1  |=================|   M1  |===================|   R1  |
    |       |<- - - - - - - - |       | - - - - - - - - - |       |
    +-------+                 +-------+ Reply Test Packet +-------+
             \                                           /
              T4                                       T3

    STAMP Session-Sender                     STAMP Session-Reflector

                     Figure 1: STAMP Reference Topology

3.  Overview

   [RFC8972] defines optional extensions for STAMP.  The optional
   extensions are added to the base STAMP test packet defined in
   [RFC8762] in the form of TLVs.  As specified in [RFC8972], both
   Session-Sender and Session-Reflector test packets are symmetric in
   size when including all optional TLVs (and excluding headers).  The
   Session-Reflector reflects all received STAMP TLVs from the Session-
   Sender test packet.

   As specified in [RFC8762], STAMP test packets are transmitted with
   IP/UDP headers.  Since midpoint nodes do not process the UDP headers
   in the packets, they are agnostic to the STAMP test packets in the
   payload.

   This document also defines a new TLV option for STAMP, called
   "Reflected MPLS Header MNA Data" (value TBA1).  When a STAMP Session-
   Sender adds an NAS in the test packet, it also adds a "Reflected MPLS
   Header MNA Data" STAMP TLV in the Session-Sender test packet with the



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   length set to the MNA Sub-Stack length (NASL) and the value field in
   the TLV initialized to zeros, in order to receive a copy of that NAS
   back in the STAMP TLV.  When adding multiple NASes in the Session-
   Sender test packet, corresponding "Reflected MPLS Header MNA Data"
   STAMP TLVs MUST be added, matching the length of the NAS and
   Ancillary Data and in the same order, in order to receive a copy of
   that NAS.

   Similarly, when a STAMP Session-Sender adds MNA PSH in the test
   packet, it also adds corresponding "Reflected MPLS Header MNA Data"
   STAMP TLV, with the matching length, in order to receive a copy of
   that MNA PSH.

   An example STAMP test packet for the MPLS data plane, carrying NASes
   and PSH and reflected MNA header data in STAMP TLVs, is shown in
   Figure 2.



































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    +---------------------------------------------------------------+
    | MPLS Header                                                   |
    ~                                                               ~
    +---------------------------------------------------------------+
    | MNA Sub-Stack-1 I-D.ietf-mpls-mna-hdr                         |
    ~                                                               ~
    +---------------------------------------------------------------+
    ~ ...                                                           ~
    +---------------------------------------------------------------+
    | MNA Sub-Stack-N I-D.ietf-mpls-mna-hdr                         |
    ~                                                               ~
    +---------------------------------------------------------------+
    ~ ...                                                           ~
    +---------------------------------------------------------------+
    | MNA Post-Stack Header I-D.ietf-mpls-mna-ps-hdr                |
    ~                                                               ~
    +---------------------------------------------------------------+
    | IP Header                                                     |
    +---------------------------------------------------------------+
    | UDP Header                                                    |
    +---------------------------------------------------------------+
    | STAMP Packet RFC 8972                                         |
    ~                                                               ~
    +---------------------------------------------------------------+
    | Reflected MPLS Header MNA Data-1 STAMP TLV (TBA1)             |
    ~                                                               ~
    +---------------------------------------------------------------+
    ~ ...                                                           ~
    +---------------------------------------------------------------+
    | Reflected MPLS Header MNA Data-M STAMP TLV (TBA1)             |
    ~                                                               ~
    +---------------------------------------------------------------+
    | Reflected MPLS Header MNA Data STAMP TLV PSH (TBA1)           |
    ~                                                               ~
    +---------------------------------------------------------------+

       Figure 2: Example STAMP Test Packet with Reflected MPLS Header
                             MNA Data STAMP TLV













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   When the Session-Reflector receives a STAMP test packet with an NAS
   and a STAMP TLV "Reflected MPLS Header MNA Data," the Session-
   Reflector that supports this STAMP TLV MUST copy the entire NAS,
   including the Ancillary Data and header, into the "Reflected MPLS
   Header MNA Data" TLV in the Session-Reflector test packet payload.
   When there are multiple NASes in the Session-Sender test packet, each
   NAS including Ancillary Data, MUST be processed, in the order from
   the top of the label stack, and copied into the corresponding STAMP
   TLV, if that STAMP TLV exists.  Similarly, the Session-Reflector MUST
   process the PSH and copy the entire PSH and the Ancillary Data into
   the corresponding STAMP TLV, if that STAMP TLV exists.

   When the Session-Reflector receives a STAMP test packet with an NAS
   or PSH but without a corresponding "Reflected MPLS Header MNA Data"
   STAMP TLV, the Session-Reflector does not copy that NAS or PSH into
   the Session-Reflector test packet.

   When the Session-Sender test packets carry an NAS or PSH in the MPLS
   header that it does not require the Session-Reflector to reflect in
   the Session-Reflector test packets, it does not add the corresponding
   "Reflected MPLS Header MNA Data" STAMP TLV in the Session-Sender test
   packets.

   If the Session-Reflector receives Session-Sender test packets with
   non-zero values in the first 8 bytes (excluding the Ancillary Data
   field that may change) in the value field of the "Reflected MPLS
   Header MNA Data" STAMP TLV, it MUST match the values in the
   corresponding NASes and the PSH in the MPLS header before copying the
   data into the STAMP TLV.  This mechanism is employed in case of
   ambiguity when there are multiple NASes and PSH in the MPLS header of
   the same length present and not all need to be copied and reflected
   in the STAMP TLVs.

   As the procedure defined in this document leverages the existing
   implementations on the midpoint nodes for the NASes and PSH, no
   additional requirements are specified when carrying NASes and PSH in
   STAMP.  The NASes and PSH are processed by the nodes using the same
   procedures specified in the document that defined them.

   The Session-Sender and Session-Reflector MUST ensure that the
   resulting STAMP test packets do not exceed the MPLS MTU after adding
   the "Reflected MPLS Header MNA Data" STAMP TLVs.  If necessary,
   "Reflected MPLS Header MNA Data" STAMP TLVs can be removed to avoid
   violating the MPLS MTU limit.







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   Note that the use case where the NAS and PSH lengths change in the
   STAMP test packets along the path is outside the scope of this
   document.  Also, the use case where the NASes and the PSH are added
   or removed in the MPLS header of the Session-Sender test packets
   along the path is outside the scope of this document.

3.1.  One-Way and Two-Way Measurement Types

   This document defines two measurement types: one-way and two-way
   measurements.

   In the two-way measurement type, the Session-Reflector adds the
   matching NASes and the PSH, including Ancillary Data, in the MPLS
   header of the Session-Reflector test packets in the same order for
   the reverse direction measurements as received in the Session-Sender
   test packets.  Whereas in the one-way measurement type, the Session-
   Reflector does not add the matching NASes and the PSH, including
   Ancillary Data, in the MPLS header of the Session-Reflector test
   packets.

3.2.  Receiving MPLS Header from the Data Plane on Egress Node

   As specified in Section 9.3, "Penultimate Node Responsibilities" of
   [I-D.ietf-mpls-mna-hdr], and Section 6.3, "Penultimate Node
   Responsibilities" of [I-D.ietf-mpls-mna-ps-hdr], for HBH and Ingress-
   to-Egress (I2E) scopes, the last copy of the NASes and the PSH MUST
   NOT be removed by the penultimate node, and hence they will be
   received by the egress node.

   Note that the NAS and the corresponding PSH for the "Select" scope
   are removed from the packets on the transit node where the NAS is
   processed, and hence they will not be received by the egress node.

   The STAMP test packets, carrying the MPLS header with the NASes and
   the PSH for HBH and I2E scopes for HBH and E2E measurements,
   respectively, will be received by the egress node hosting the
   Session-Reflector.  When the received STAMP test packets are
   processed by the data plane on the egress node that has the Session-
   Reflector, the data plane MUST provide the received MPLS header
   containing the NASes and the PSH from the Session-Sender test packets
   to the Session-Reflector on the node.

   Similarly, when the received STAMP test packets are processed by the
   data plane on the egress node in the reverse direction that has the
   Session-Sender, the data plane MUST provide the received MPLS header
   containing the NASes and the PSH from the Session-Reflector test
   packets to the Session-Sender on the node for the two-way measurement
   type.



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4.  Use Case of Reflecting IOAM Data Fields

   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 IOAM data fields are defined in [RFC9197].  Examples of data
   recorded by IOAM Trace Options include per-hop information, such as
   node ID, timestamp, queue depth, interface ID, interface load, etc.
   The information collected can be used for monitoring ECMP paths,
   proof-of-transit, and troubleshooting failures in the network.  IOAM
   can be used with STAMP test packets for active measurement.  The
   procedure and STAMP extensions defined in this document can be used
   to reflect the collected IOAM data fields back to the Sender, where
   the Sender can use that information to support the hop-by-hop and
   edge-to-edge measurement use cases.

   [I-D.ietf-mpls-mna-ioam] defines extensions using MNA to carry IOAM
   data that may be carried in NAS [I-D.ietf-mpls-mna-hdr] or in PSH
   [I-D.ietf-mpls-mna-ps-hdr].  The STAMP Session-Sender and Session-
   Reflector test packets can carry an NAS and PSH for HBH and E2E
   operational and telemetry information for active measurement, as
   shown in Figure 3, as an example.

    +---------------------------------------------------------------+
    | MPLS Header                                                   |
    +---------------------------------------------------------------+
    | IOAM MNA Sub-Stack I-D.ietf-mpls-mna-ioam                     |
    ~                                                               ~
    +---------------------------------------------------------------+
    | IOAM MNA PSH I-D.ietf-mpls-mna-ioam                           |
    ~                                                               ~
    +---------------------------------------------------------------+
    | IP Header                                                     |
    +---------------------------------------------------------------+
    | UDP Header                                                    |
    +---------------------------------------------------------------+
    | STAMP Packet RFC 8972                                         |
    +---------------------------------------------------------------+
    | Reflected MPLS Header MNA Data STAMP TLV (TBA1)               |
    ~                                                               ~
    +---------------------------------------------------------------+
    | Reflected MPLS Header MNA Data STAMP TLV PSH (TBA1)           |
    ~                                                               ~
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Figure 3: Example STAMP Test Packet for IOAM with Reflected MPLS
                            Header MNA Data TLV




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5.  STAMP Extensions

5.1.  Reflected MPLS Header MNA Data TLV

   The "Reflected MPLS Header MNA Data" STAMP TLV is carried by Session-
   Sender and Session-Reflector test packets.  STAMP test packets may
   carry multiple TLVs of this type.  The format of the "Reflected MPLS
   Header MNA Data" TLV is shown in Figure 4.

     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
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |STAMP TLV Flags|  Type=TBA1    |         Length                |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                  Reflected MPLS Header MNA Data               |
    ~                                                               ~
    |                                                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             Figure 4: Reflected MPLS Header MNA Data STAMP TLV

   The TLV fields are defined as follows:

   Type: Type (value TBA1)

   STAMP TLV Flags: The STAMP TLV Flags follow the procedures described
   in [RFC8972].

   Length: A two-octet field equal to the length of the Data in octets.

   If, due to some error, such as a mismatch in the length between the
   NAS or PSH and the Reflected MPLS header MNA data TLV, and the
   Session-Reflector does not use the received "Reflected MPLS Header
   MNA Data" STAMP TLV for reflecting MPLS header, it MUST return the
   STAMP TLV with the U flag (Unrecognized) set to 1 in the STAMP TLV
   Flags using the procedure defined in [RFC8972].

5.2.  MNA Header Control Sub-TLV

   In this document, the Sub-TLV "MNA Header Control" (Type TBA2) is
   defined for the STAMP TLV Type "Reflected Test Packet Control" (Type
   12) introduced in [I-D.ietf-ippm-asymmetrical-pkts].

   When a Session-Sender test packet is received with the "MNA Header
   Control" Sub-TLV, the Session-Reflector does not add the NASes and
   the PSH in the MPLS header of the reply Session-Reflector STAMP test
   packet that match the received NASes and the PSH.




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   In the absence of this Sub-TLV in the received Session-Sender test
   packet, the Session-Reflector adds the new NASes and the PSH that
   match all received NASes and the PSH in the MPLS header of the reply
   Session-Reflector test packet.

   The NASes and the PSH received in the Session-Sender test packets are
   still copied and reflected in STAMP TLVs to the Session-Sender
   irrespective of this Sub-TLV present or not.

6.  Operational Considerations

   The operational considerations specified in [RFC8762] and
   [I-D.ietf-mpls-mna-hdr] apply to the procedure and extensions defined
   in this document.

7.  Security Considerations

   The security considerations specified in [RFC8762], [RFC8972],
   [I-D.ietf-mpls-mna-hdr] and [I-D.ietf-mpls-mna-ps-hdr] apply to the
   procedure and extensions defined in this document.  In addition, the
   security considerations specified in [RFC9197] and
   [I-D.ietf-mpls-mna-ioam] also apply when using them.

8.  Implementation Status

   Editorial note: Please remove this section prior to publication.

   An open-source implementation of STAMP with optional TLVs [RFC8972],
   MPLS Network Action (with In-Stack and Post-Stack Data), and IOAM
   pre-allocated trace option [RFC9197] for one-way and two-way
   measurement types for Hop-by-Hop delay measurement (for 4 transit
   nodes) using the extensions defined in this document is available in
   the Tofino2.

   https://github.com/uni-tue-kn/stamp-mpls-mna-poc

   Contact:

   Fabian Ihle

   University of Tuebingen

   Germany

   Email: fabian.ihle@uni-tuebingen.de






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9.  IANA Considerations

   IANA has created the "STAMP TLV Types" registry for [RFC8972].  IANA
   is requested to allocate a value for the "Reflected MPLS Header MNA
   Data" TLV Type from the IETF Review TLV range of the same registry.

        +=======+================================+===============+
        | Value |          Description           | Reference     |
        +=======+================================+===============+
        | TBA1  | Reflected MPLS Header MNA Data | This document |
        +-------+--------------------------------+---------------+

                         Table 1: STAMP TLV Type

   IANA is requested to allocate a value for the Sub-TLV Type "MNA
   Header Control" (Type TBA2) for the STAMP TLV Type "Reflected Test
   Packet Control" (Type 12) defined in
   [I-D.ietf-ippm-asymmetrical-pkts], from the "STAMP Sub-TLV Types"
   registry.

        +=======+====================+================+===========+
        | Value |    Description     |    TLV Used    | Reference |
        +=======+====================+================+===========+
        | TBA2  | MNA Header Control | Reflected Test | This      |
        |       |                    | Packet Control | document  |
        +-------+--------------------+----------------+-----------+

          Table 2: Sub-TLV Type for Reflected Test Packet Control
                                 STAMP TLV

10.  References

10.1.  Normative References

   [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>.

   [RFC8762]  Mirsky, G., Jun, G., Nydell, H., and R. Foote, "Simple
              Two-Way Active Measurement Protocol", RFC 8762,
              DOI 10.17487/RFC8762, March 2020,
              <https://www.rfc-editor.org/info/rfc8762>.




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   [RFC8972]  Mirsky, G., Min, X., Nydell, H., Foote, R., Masputra, A.,
              and E. Ruffini, "Simple Two-Way Active Measurement
              Protocol Optional Extensions", RFC 8972,
              DOI 10.17487/RFC8972, January 2021,
              <https://www.rfc-editor.org/info/rfc8972>.

   [I-D.ietf-mpls-mna-hdr]
              Rajamanickam, J., Gandhi, R., Zigler, R., Song, H., and K.
              Kompella, "MPLS Network Action (MNA) Sub-Stack
              Specification including In-Stack Network Actions and
              Data", Work in Progress, Internet-Draft, draft-ietf-mpls-
              mna-hdr-21, 24 February 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-mpls-
              mna-hdr-21>.

   [I-D.ietf-mpls-mna-ps-hdr]
              Rajamanickam, J., Gandhi, R., Zigler, R., Dong, J., and J.
              Bhattacharya, "Post-Stack MPLS Network Action (MNA) Header
              Specification", Work in Progress, Internet-Draft, draft-
              ietf-mpls-mna-ps-hdr-08, 2 April 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-mpls-
              mna-ps-hdr-08>.

   [I-D.ietf-mpls-mna-ioam]
              Gandhi, R., Mirsky, G., Li, T., Song, H., and B. Wen,
              "Supporting In Situ Operations, Administration and
              Maintenance Using MPLS Network Actions", Work in Progress,
              Internet-Draft, draft-ietf-mpls-mna-ioam-05, 19 May 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-mpls-
              mna-ioam-05>.

   [I-D.ietf-ippm-asymmetrical-pkts]
              Mirsky, G., Ruffini, E., Nydell, H., Foote, R. F., and W.
              Hawkins, "Performance Measurement with Asymmetrical
              Traffic Using Simple Two-Way Active Measurement Protocol
              (STAMP)", Work in Progress, Internet-Draft, draft-ietf-
              ippm-asymmetrical-pkts-14, 16 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-ippm-
              asymmetrical-pkts-14>.

10.2.  Informative References

   [RFC9197]  Brockners, F., Ed., Bhandari, S., Ed., and T. Mizrahi,
              Ed., "Data Fields for In Situ Operations, Administration,
              and Maintenance (IOAM)", RFC 9197, DOI 10.17487/RFC9197,
              May 2022, <https://www.rfc-editor.org/info/rfc9197>.





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Internet-Draft   STAMP Reflecting MPLS Extension Headers       June 2026


Acknowledgments

   The authors of this document would like to thank Greg Mirsky for
   reviewing this document and providing review comments.  The authors
   would also like to thank Fabian Ihle for implementing the solution
   defined in this document in Tofino2.

Authors' Addresses

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


   Tianran Zhou
   Huawei
   China
   Email: zhoutianran@huawei.com


   Zhenqiang Li
   China Mobile
   China
   Email: lizhenqiang@chinamobile.com


   Fabian Ihle
   University of Tuebingen
   Tuebingen
   Germany
   Email: fabian.ihle@uni-tuebingen.de



















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