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One-way/Two-way Active Measurement Protocol Extensions for Performance Measurement on LAG
draft-li-ippm-otwamp-on-lag-03

Document Type Active Internet-Draft (individual)
Authors Zhenqiang Li , Tianran Zhou , Guo Jun , Greg Mirsky , Rakesh Gandhi
Last updated 2022-03-06
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draft-li-ippm-otwamp-on-lag-03
Network Working Group                                              Z. Li
Internet-Draft                                              China Mobile
Intended status: Standards Track                                 T. Zhou
Expires: 8 September 2022                                         Huawei
                                                                  J. Guo
                                                               ZTE Corp.
                                                               G. Mirsky
                                                                Ericsson
                                                               R. Gandhi
                                                                   Cisco
                                                            7 March 2022

 One-way/Two-way Active Measurement Protocol Extensions for Performance
                           Measurement on LAG
                     draft-li-ippm-otwamp-on-lag-03

Abstract

   This document defines extensions to One-way Active Measurement
   Protocol (OWAMP), and Two-way Active Measurement Protocol (TWAMP) to
   implement performance measurement on every member link of a Link
   Aggregation Group (LAG).  Knowing the measured metrics of each member
   link of a LAG enables operators to enforce the performance based
   traffic steering policy across the member links.

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

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."

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   This Internet-Draft will expire on 8 September 2022.

Copyright Notice

   Copyright (c) 2022 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  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Micro Session on LAG  . . . . . . . . . . . . . . . . . . . .   3
   3.  Mirco OWAMP Session . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  Micro OWAMP-Control . . . . . . . . . . . . . . . . . . .   4
     3.2.  Micro OWAMP-Test  . . . . . . . . . . . . . . . . . . . .   4
   4.  Mirco TWAMP Session . . . . . . . . . . . . . . . . . . . . .   5
     4.1.  Micro TWAMP-Control . . . . . . . . . . . . . . . . . . .   5
     4.2.  Micro TWAMP-Test  . . . . . . . . . . . . . . . . . . . .   5
       4.2.1.  Sender Packet Format and Content  . . . . . . . . . .   5
       4.2.2.  Sender Behavior . . . . . . . . . . . . . . . . . . .   7
       4.2.3.  Reflector Packet Format and Content . . . . . . . . .   8
       4.2.4.  Reflector Behavior  . . . . . . . . . . . . . . . . .  11
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
     5.1.  Mico OWAMP-Control Command  . . . . . . . . . . . . . . .  11
     5.2.  Mico TWAMP-Control Command  . . . . . . . . . . . . . . .  11
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  12
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  12
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   Link Aggregation Group (LAG), as defined in [IEEE802.1AX], provides
   mechanisms to combine multiple physical links into a single logical
   link.  This logical link offers higher bandwidth and better
   resiliency, because if one of the physical member links fails, the
   aggregate logical link can continue to forward traffic over the
   remaining operational physical member links.

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   Usually, when forwarding traffic over LAG, the hash-based mechanism
   is used to load balance the traffic across the LAG member links.
   Link delay of each member link varies because of different transport
   paths.  To provide low latency service for time sensitive traffic, we
   need to explicitly steer the traffic across the LAG member links
   based on the link delay, loss and so on.  That requires a solution to
   measure the performance metrics of every member link of a LAG.  Hence
   the measured performance metrics can work together with layer 2
   bundle member link attributes advertisement [RFC8668] for traffic
   steering.

   OWAMP [RFC4656] and TWAMP [RFC5357] are two active measurement
   methods according to the classification given in [RFC7799], which can
   complement passive and hybrid methods.  With both methods, running a
   single test session over the aggregation without the knowledge of
   each member link would make it impossible to measure the performance
   of a given physical member link.  The measured metrics can only
   reflect the performance of one member link or an average of some/all
   member links of the LAG.

   This document extends OWAMP and TWAMP to implement performance
   measurement on every member link of a LAG.  The proposed method could
   also potentially apply to layer 3 ECMP (Equal Cost Multi-Path), e.g.,
   with SR-Policy [I-D.ietf-spring-segment-routing-policy].

2.  Micro Session on LAG

   This document intends to address the scenario (e.g., Figure 1) where
   a LAG (e.g., the LAG includes four member links) directly connects
   two nodes (A and B).  The goal is to measure the performance of each
   link of the LAG.

                     +---+                       +---+
                     |   |-----------------------|   |
                     | A |-----------------------| B |
                     |   |-----------------------|   |
                     |   |-----------------------|   |
                     +---+                       +---+

                            Figure 1: PM for LAG

   To measure the performance metrics of every member link of a LAG,
   multiple sessions (one session for each member link) need to be
   established between the two end points that are connected by the LAG.
   These sessions are called micro sessions in the remainder of this
   document.

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   All micro sessions of a LAG share the same Sender IP Address and
   Receiver IP Address.  As for the UDP layer, the micro sessions may
   share the same Sender Port and Receiver Port pair, or each micro
   session is configured with a different Sender Port and Receiver Port
   pair.  But from the operational point of view, the former is simpler
   and is RECOMMENDED.

   The micro sessions need to associate with the corresponding member
   links.  For example, when the Server/Reflector/Receiver receives a
   Test packet, it needs to know from which member link the packet is
   received, and correlate it with a micro session.

   This document defines new command types to indicate the set of micro
   sessions of a LAG.  The details are described in Sections 3 and 4 of
   this document.  Upon receiving a Test packet, the receiver uses the
   receiving link's identifier to correlate the packet to a particular
   micro session.  In addition, Test packets MAY carry the member link
   information for validation check.  For example, when a micro Session-
   Sender receives a reflected Test packet, it may need to check whether
   the Test packet is from the expected member link.

3.  Mirco OWAMP Session

   This document assumes that the OWAMP Server and the OWAMP Receiver of
   an OWAMP micro session are at the same end point.

3.1.  Micro OWAMP-Control

   To support the micro OWAMP session, a new command, Request-OW-Micro-
   Sessions (TBD1), is defined in this document.  The Request-OW-Micro-
   Sessions command is based on the OWAMP Request-Session command, and
   uses the message format as described in Section 3.5 of OWAMP
   [RFC4656].  Test session creation of micro OWAMP session follows the
   same procedure as defined in Section 3.5 of OWAMP [RFC4656] with the
   following additions:

   When an OWAMP Server receives a Request-OW-Micro-Sessions command, if
   the request is accepted, the OWAMP Server MUST build a set of micro
   sessions for all the member links of the LAG from which the Request-
   OW-Micro-Sessions message is received.

3.2.  Micro OWAMP-Test

   Micro OWAMP-Test reuses the OWAMP-Test packet format and procedures
   as defined in Section 4 of OWAMP [RFC4656] with the following
   additions:

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   The micro OWAMP Sender MUST send the micro OWAMP-Test packets over
   the member link with which the session is associated.  When receives
   a Test packet, the micro OWAMP receiver MUST use the member link from
   which the Test packet is received to correlate the micro OWAMP
   session.  If there is no such a session, the Test packet MUST be
   discarded.

4.  Mirco TWAMP Session

   As above, this document assumes that the TWAMP Server and the TWAMP
   Session-Reflector of a micro OWAMP session are at the same end point.

4.1.  Micro TWAMP-Control

   To support the micro TWAMP session, a new command, Request-TW-Micro-
   Sessions (TBD2), is defined in this document.  The Request-TW-Micro-
   Sessions command is based on the TWAMP Request-Session command, and
   uses the message format as described in Section 3.5 of TWAMP
   [RFC5357].  Test session creation of micro TWAMP session follows the
   same procedure as defined in Section 3.5 of TWAMP [RFC5357] with the
   following additions:

   When a TWAMP Server receives a Request-TW-Micro-Sessions command, if
   the request is accepted, the TWAMP Server MUST build a set of micro
   sessions for all the member links of the LAG from which the Request-
   TW-Micro-Sessions message is received.

4.2.  Micro TWAMP-Test

   The micro TWAMP-Test protocol is based on the TWAMP-Test protocol
   [RFC5357] with the following extensions.

4.2.1.  Sender Packet Format and Content

   The micro TWAMP Session-Sender packet format is based on the TWAMP
   Session-Sender packet format as defined in Section 4.1.2 of
   [RFC5357].  Two new fields (Sender Micro-session ID and Reflector
   Micro-session ID) are added to carry the LAG member link identifiers.

   For unauthenticated mode, the format is as below:

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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Sequence Number                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                          Timestamp                            |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Error Estimate         |             MBZ               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Sender Micro-session ID    |   Reflector Micro-session ID  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       .                         Packet Padding                        .
       .                                                               .
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure 2: Micro Session-Sender Packet format in Unauthenticated Mode

   For authenticated mode, the format is as below:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Sequence Number                        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       |                        MBZ (12 octets)                        |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                          Timestamp                            |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Error Estimate         |              MBZ              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Sender Micro-session ID    |   Reflector Micro-session ID  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       |                       HMAC (16 octets)                        |
       |                                                               |
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                                                               |
       .                        Packet Padding                         .
       .                                                               .
       |                                                               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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    Figure 3: Micro Session-Sender Packet Format in Authenticated Mode

   Except for the Sender/Reflector Micro-session ID field, all the other
   fields are the same as defined in Section 4.1.2 of TWAMP [RFC5357],
   which is defined in Section 4.1.2 of OWAMP [RFC4656].  Therefore, it
   follows the same procedure and guidelines as defined in Section 4.1.2
   of TWAMP [RFC5357].

   *  Sender Micro-session ID (2-octets in length): it is defined to
      carry the Micro-session identifier of the Sender side.  The value
      of the Sender Micro-session ID MUST be unique at the Session-
      Sender.

   *  Reflector Micro-session ID (2-octets in length): it is defined to
      carry the Micro-session identifier of the Reflector side.  The
      value of the Reflector Micro-session ID MUST be unique at the
      Session-Reflector.

4.2.2.  Sender Behavior

   The micro TWAMP Session-Sender inherits the behaviors of the TWAMP
   Session-Reflector as defined in Section 4.1 of [RFC5357].  In
   addition, the micro TWAMP Session-Sender MUST send the micro TWAMP-
   Test packets over the member link with which the session is
   associated.

   When sending the Test packet, the micro TWAMP Session-Sender MUST put
   the Sender member link identifier that is associated with the micro
   TWAMP session in the Sender Micro-session ID.  If the Session-Sender
   knows the Reflector member link identifier, the Reflector Micro-
   session ID field (see Figure 2 and Figure 3) MUST be set.  Otherwise,
   the Reflector Micro-session ID field MUST be zero.

   A Test packet with Sender member link identifier is sent to the
   Session-Reflector, and then is reflected with the same Sender member
   link identifier.  So the Session-Sender can use the Sender member
   link identifier to check whether a reflected Test packet is received
   from the member link associated with the correct micro TWAMP session.

   The Reflector member link identifier carried in the Reflector Micro-
   session ID field is used by the Session-Receiver to check whether a
   Test packet is received from the member link associated with the
   correct micro TWAMP session.  It means that the Session-Sender has to
   learn the Reflector member link identifier.  Once the Session-Sender
   knows the Reflector member link identifier, it MUST put the
   identifier in the Reflector Micro-session ID field (see Figure 2 or
   Figure 3) of the Test packets that will be sent to the Session-

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   Reflector.  The Reflector member link identifier can be obtained from
   pre-configuration or learned from the data plane (e.g., the reflected
   Test packet).  How to obtain/learn the Reflector member link
   identifier is out of the scope of this document.

   When receiving a reflected Test packet, the micro TWAMP Session-
   Sender MUST use the receiving member link to correlate the reflected
   Test packet to a micro TWAMP session.  If there is no such a session,
   the reflected Test packet MUST be discarded.  If a matched session
   exists, the micro Session-Sender MUST use the Sender Micro-session ID
   to validate whether the reflected Test packet is correctly
   transmitted over the expected member link.  If the validation fails,
   the Test packet MUST be discarded.  The micro Session-Sender MUST use
   the Reflector Micro-session ID to validate the Reflector's behavior.
   If the validation fails, the Test packet MUST be discarded.

4.2.3.  Reflector Packet Format and Content

   The micro TWAMP Session-Reflector packet format is based on the TWAMP
   Session-Reflector packet format as defined in Section 4.2.1 of
   [RFC5357].  Two new fields (Sender and Reflector Micro-session ID)
   are added to carry the LAG member link identifiers.

   For unauthenticated mode, the format is as below:

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      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Sequence Number                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          Timestamp                            |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         Error Estimate        |               MBZ             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       Receive Timestamp                       |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      Sender Sequence Number                   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       Sender Timestamp                        |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |      Sender Error Estimate    |    Sender Micro-session ID    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Sender TTL   |      MBZ      |   Reflector Micro-session ID  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      .                                                               .
      .                         Packet Padding                        .
      .                                                               .
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             Figure 4: Micro Session-Reflector Packet Format in
                            Unauthenticated Mode

   For authenticated mode, the format is as below:

      0                   1                   2                   3
      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Sequence Number                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        MBZ (12 octets)                        |
      |                                                               |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          Timestamp                            |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         Error Estimate        |               MBZ             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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      |    Sender Micro-session ID    |   Reflector Micro-session ID  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Receive Timestamp                      |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        MBZ (8 octets)                         |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Sender Sequence Number                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        MBZ (12 octets)                        |
      |                                                               |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      Sender Timestamp                         |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |      Sender Error Estimate    |                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
      |                        MBZ (6 octets)                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Sender TTL   |                                               |
      +-+-+-+-+-+-+-+-+                                               +
      |                                                               |
      |                                                               |
      |                        MBZ (15 octets)                        |
      +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
      |                        HMAC (16 octets)                       |
      |                                                               |
      |                                                               |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      .                         Packet Padding                        .
      .                                                               .
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure 5: Micro Session-Reflector Packet Format in Authenticated Mode

   Except for the Sender/Reflector Micro-session ID field, all the other
   fields are the same as defined in Section 4.2.1 of TWAMP [RFC5357].
   Therefore, it follows the same procedure and guidelines as defined in
   Section 4.2.1 of TWAMP [RFC5357].

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   *  Sender Micro-session ID (2-octets in length): it is defined to
      carry the Micro-session identifier of the Sender side.  The value
      of the Sender Micro-session ID MUST be unique at the Session-
      Sender.

   *  Reflector Micro-session ID (2-octets in length): it is defined to
      carry the Micro-session identifier of the Reflector side.  The
      value of the Reflector Micro-session ID MUST be unique at the
      Session-Reflector.

4.2.4.  Reflector Behavior

   The micro TWAMP Session-Reflector inherits the behaviors of a TWAMP
   Session-Reflector as defined in Section 4.2 of [RFC5357].

   In addition, when receiving a Test packet, the micro TWAMP Session-
   Reflector MUST use the receiving member link to correlate the Test
   packet to a micro TWAMP session.  If there is no such a session, the
   Test packet MUST be discarded.  If the Reflector Micro-session ID is
   not zero, the Reflector MUST use the Reflector Micro-session ID to
   validate whether it associates with the receiving member link.  If
   the validation fails, the Test packet MUST be discarded.

   When sending a response to the received Test packet, the micro TWAMP
   Session-Reflector MUST copy the Sender member link identifier from
   the received Test packet and put it in the Sender Micro-session ID
   field of the reflected Test packet (see Figure 4 and Figure 5).  In
   addition, the micro TWAMP Session-Reflector MUST fill the Reflector
   Micro-session ID field (see Figure 2 and Figure 3) of the reflected
   Test packet with the member link identifier that is associated with
   the micro TWAMP session.

5.  IANA Considerations

5.1.  Mico OWAMP-Control Command

   This document requires the IANA to allocate the following command
   type from OWAMP-Control Command Number Registry.

   Value  Description                   Semantics Definition
   TBD1   Request-OW-Micro-Sessions     This document, Section 3.1

5.2.  Mico TWAMP-Control Command

   This document requires the IANA to allocate the following command
   type from TWAMP-Control Command Number Registry.

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   Value  Description                   Semantics Definition
   TBD2   Request-TW-Micro-Sessions     This document, Section 4.1

6.  Security Considerations

   This document does not introduce additional security requirements and
   mechanisms other than those described in [RFC4656], and [RFC5357].

7.  Acknowledgements

   The authors would like to thank Fang Xin, Henrik Nydell, Mach Chen,
   Min Xiao, Jeff Tantsura for the valuable comments to this work.

8.  References

8.1.  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>.

   [RFC4656]  Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M.
              Zekauskas, "A One-way Active Measurement Protocol
              (OWAMP)", RFC 4656, DOI 10.17487/RFC4656, September 2006,
              <https://www.rfc-editor.org/info/rfc4656>.

   [RFC5357]  Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J.
              Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)",
              RFC 5357, DOI 10.17487/RFC5357, October 2008,
              <https://www.rfc-editor.org/info/rfc5357>.

   [RFC7799]  Morton, A., "Active and Passive Metrics and Methods (with
              Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799,
              May 2016, <https://www.rfc-editor.org/info/rfc7799>.

   [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>.

   [RFC8668]  Ginsberg, L., Ed., Bashandy, A., Filsfils, C., Nanduri,
              M., and E. Aries, "Advertising Layer 2 Bundle Member Link
              Attributes in IS-IS", RFC 8668, DOI 10.17487/RFC8668,
              December 2019, <https://www.rfc-editor.org/info/rfc8668>.

8.2.  Informative References

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   [I-D.ietf-spring-segment-routing-policy]
              Filsfils, C., Talaulikar, K., Voyer, D., Bogdanov, A., and
              P. Mattes, "Segment Routing Policy Architecture", Work in
              Progress, Internet-Draft, draft-ietf-spring-segment-
              routing-policy-18, 17 February 2022,
              <https://www.ietf.org/archive/id/draft-ietf-spring-
              segment-routing-policy-18.txt>.

   [IEEE802.1AX]
              IEEE Std. 802.1AX, "IEEE Standard for Local and
              metropolitan area networks - Link Aggregation", November
              2008.

Authors' Addresses

   Zhenqiang Li
   China Mobile
   China
   Email: li_zhenqiang@hotmail.com

   Tianran Zhou
   Huawei
   China
   Email: zhoutianran@huawei.com

   Jun Guo
   ZTE Corp.
   China
   Email: guo.jun2@zte.com.cn

   Greg Mirsky
   Ericsson
   United States of America
   Email: gregimirsky@gmail.com

   Rakesh Gandhi
   Cisco
   Canada
   Email: rgandhi@cisco.com

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