Simple Two-way Active Measurement Protocol
draft-ietf-ippm-stamp-06

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Network Working Group                                          G. Mirsky
Internet-Draft                                                 ZTE Corp.
Intended status: Standards Track                                  G. Jun
Expires: October 25, 2019                                ZTE Corporation
                                                               H. Nydell
                                                       Accedian Networks
                                                                R. Foote
                                                                   Nokia
                                                          April 23, 2019

               Simple Two-way Active Measurement Protocol
                        draft-ietf-ippm-stamp-06

Abstract

   This document describes a Simple Two-way Active Measurement Protocol
   which enables the measurement of both one-way and round-trip
   performance metrics like delay, delay variation, and packet loss.

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 October 25, 2019.

Copyright Notice

   Copyright (c) 2019 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
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   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must

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   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions used in this document . . . . . . . . . . . . . .   3
     2.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
     2.2.  Requirements Language . . . . . . . . . . . . . . . . . .   3
   3.  Softwarization of Performance Measurement . . . . . . . . . .   3
   4.  Theory of Operation . . . . . . . . . . . . . . . . . . . . .   4
     4.1.  Session-Sender Behavior and Packet Format . . . . . . . .   4
       4.1.1.  Session-Sender Packet Format in Unauthenticated Mode    4
       4.1.2.  Session-Sender Packet Format in Authenticated Mode  .   6
     4.2.  Session-Reflector Behavior and Packet Format  . . . . . .   7
       4.2.1.  Session-Reflector Packet Format in Unauthenticated
               Mode  . . . . . . . . . . . . . . . . . . . . . . . .   8
       4.2.2.  Session-Reflector Packet Format in Authenticated Mode   9
     4.3.  Integrity and Confidentiality Protection in STAMP . . . .  11
     4.4.  Interoperability with TWAMP Light . . . . . . . . . . . .  11
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   7.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  12
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  12
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   Development and deployment of Two-Way Active Measurement Protocol
   (TWAMP) [RFC5357] and its extensions, e.g., [RFC6038] that defined
   features such as Reflect Octets and Symmetrical Size for TWAMP
   provided invaluable experience.  Several independent implementations
   exist, have been deployed and provide important operational
   performance measurements.  At the same time, there has been
   noticeable interest in using a simpler mechanism for active
   performance monitoring that can provide deterministic behavior and
   inherit separation of control (vendor-specific configuration or
   orchestration) and test functions.  One of such is Performance
   Measurement from IP Edge to Customer Equipment using TWAMP Light from
   Broadband Forum [BBF.TR-390] used as the reference TWAMP Light that,
   according to [RFC8545], includes sub-set of TWAMP-Test functions in
   combination with other applications that provide, for example,
   control and security.  This document defines active performance
   measurement test protocol, Simple Two-way Active Measurement Protocol

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   (STAMP), that enables measurement of both one-way and round-trip
   performance metrics like delay, delay variation, and packet loss.

2.  Conventions used in this document

2.1.  Terminology

   AES Advanced Encryption Standard

   CBC Cipher Block Chaining

   ECB Electronic Cookbook

   KEK Key-encryption Key

   STAMP - Simple Two-way Active Measurement Protocol

   NTP - Network Time Protocol

   PTP - Precision Time Protocol

   HMAC Hashed Message Authentication Code

   OWAMP One-Way Active Measurement Protocol

   TWAMP Two-Way Active Measurement Protocol

2.2.  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.

3.  Softwarization of Performance Measurement

   Figure 1 presents the Simple Two-way Active Measurement Protocol
   (STAMP) Session-Sender and Session-Reflector with a measurement
   session.  The configuration and management of the STAMP Session-
   Sender, Session-Reflector and management of the STAMP sessions can be
   achieved through various means.  Command Line Interface, OSS/BSS
   (operations support system/business support system as a combination
   of two systems used to support a range of telecommunication services)
   using SNMP or controllers in Software-Defined Networking using
   Netconf/YANG are but a few examples.

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         o----------------------------------------------------------o
         |                      Configuration and                   |
         |                         Management                       |
         o----------------------------------------------------------o
                ||                                          ||
                ||                                          ||
                ||                                          ||
     +----------------------+                +-------------------------+
     | STAMP Session-Sender | <--- STAMP---> | STAMP Session-Reflector |
     +----------------------+                +-------------------------+

                      Figure 1: STAMP Reference Model

4.  Theory of Operation

   STAMP Session-Sender transmits test packets toward STAMP Session-
   Reflector.  STAMP Session-Reflector receives Session-Sender's packet
   and acts according to the configuration and optional control
   information communicated in the Session-Sender's test packet.  STAMP
   defines two different test packet formats, one for packets
   transmitted by the STAMP-Session-Sender and one for packets
   transmitted by the STAMP-Session-Reflector.  STAMP supports two
   modes: unauthenticated and authenticated.  Unauthenticated STAMP test
   packets, defined in Section 4.1.1 and Section 4.2.1, ensure
   interworking between STAMP and TWAMP Light as described in
   Section 4.4 packet formats.

   By default, STAMP uses symmetrical packets, i.e., size of the packet
   transmitted by Session-Reflector equals the size of the packet
   received by the Session-Reflector.

4.1.  Session-Sender Behavior and Packet Format

   Because STAMP supports symmetrical test packets, STAMP Session-Sender
   packet has a minimum size of 44 octets in unauthenticated mode, see
   Figure 2, and 112 octets in the authenticated mode, see Figure 4.

4.1.1.  Session-Sender Packet Format in Unauthenticated Mode

   STAMP Session-Sender packet format in unauthenticated mode:

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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 (27 octets)                       |
      |                                                               |
      |                                                               |
      |                                                               |
      +               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |               |          Server Octets        |               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+               +
      |           Remaining Packet Padding (to be reflected)          |
      ~          (length in octets specified in Server Octets)        ~
      +                                               +-+-+-+-+-+-+-+-+
      |                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure 2: STAMP Session-Sender test packet format in unauthenticated
                                   mode

   where fields are defined as the following:

   o  Sequence Number is four octets long field.  For each new session
      its value starts at zero and is incremented with each transmitted
      packet.

   o  Timestamp is eight octets long field.  STAMP node MUST support
      Network Time Protocol (NTP) version 4 64-bit timestamp format
      [RFC5905], the format used in [RFC5357].  STAMP node MAY support
      IEEE 1588v2 Precision Time Protocol truncated 64-bit timestamp
      format [IEEE.1588.2008], the format used in [RFC8186].

   o  Error Estimate is two octets long field with format displayed in
      Figure 3

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            0                   1
            0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           |S|Z|   Scale   |   Multiplier  |
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                      Figure 3: Error Estimate Format

      where S, Scale, and Multiplier fields are interpreted as they have
      been defined in section 4.1.2 [RFC4656]; and Z field - as has been
      defined in section 2.3 [RFC8186]:

      *  0 - NTP 64 bit format of a timestamp;

      *  1 - PTPv2 truncated format of a timestamp.

      The STAMP Session-Sender and Session-Reflector MAY use, not use,
      or set value of the Z field in accordance with the timestamp
      format in use.  This optional field is to enhance operations, but
      local configuration or defaults could be used in its place.

   o  Must-be-Zero (MBZ) field in the session-sender unauthenticated
      packet is 27 octets long.  It MUST be all zeroed on the
      transmission and ignored on receipt.

   o  Server Octets field is optional two octets long field.  This field
      is used for the Reflect Octets capability defined in [RFC6038].
      If being used, the Server Octets field MUST follow the 27 octets
      long MBZ field.  The value in the Server Octets field equals the
      number of octets the Session-Reflector is expected to copy back to
      the Session-Sender starting with the Server Octets field.  Thus
      the minimum non-zero value for the Server Octets field is two.
      Therefore, the value of one is invalid.  If none of Payload to be
      copied, the value of the Server Octets field MUST be set to zero
      on transmit.

   o  Remaining Packet Padding is an optional field of variable length.
      The number of octets in the Remaining Packet Padding field is the
      value of the Server Octets field minus the length of the Server
      Octets field.

4.1.2.  Session-Sender Packet Format in Authenticated Mode

   STAMP Session-Sender packet format in authenticated mode:

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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                          |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                                                               |
    |                      MBZ (12 octets)                          |
    |                                                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                        Timestamp                              |
    |                                                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |        Error Estimate         |                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
    ~                                                               ~
    |                         MBZ (70 octets)                       |
    ~                                                               ~
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                                                               |
    |                       HMAC (16 octets)                        |
    |                                                               |
    |                                                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

    Figure 4: STAMP Session-Sender test packet format in authenticated
                                   mode

   The field definitions are the same as the unauthenticated mode,
   listed in Section 4.1.1.  Also, Comp.MBZ field is a variable length
   field to align the packet on 16 octets boundary.  Also, the packet
   includes a key-hashed message authentication code (HMAC) ([RFC2104])
   hash at the end of the PDU.  The detailed use of the HMAC field is
   described in Section 4.3.

4.2.  Session-Reflector Behavior and Packet Format

   The Session-Reflector receives the STAMP test packet, verifies it,
   prepares and transmits the reflected test packet.

   Two modes of STAMP Session-Reflector characterize the expected
   behavior and, consequently, performance metrics that can be measured:

   o  Stateless - STAMP Session-Reflector does not maintain test state
      and will reflect the received sequence number without
      modification.  As a result, only round-trip packet loss can be
      calculated while the reflector is operating in stateless mode.

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   o  Stateful - STAMP Session-Reflector maintains test state thus
      enabling the ability to determine forward loss, gaps recognized in
      the received sequence number.  As a result, both near-end
      (forward) and far-end (backward) packet loss can be computed.
      That implies that the STAMP Session-Reflector MUST keep a state
      for each accepted STAMP-test session, uniquely identifying STAMP-
      test packets to one such session instance, and enabling adding a
      sequence number in the test reply that is individually incremented
      on a per-session basis.

4.2.1.  Session-Reflector Packet Format in Unauthenticated Mode

   For unauthenticated mode:

     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                    |
    |                                                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                 Session-Sender Sequence Number                |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |                  Session-Sender Timestamp                     |
    |                                                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    | Session-Sender Error Estimate |           MBZ                 |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |Ses-Sender TTL |                                               |
    +-+-+-+-+-+-+-+-+                                               +
    |                                                               |
    ~                Packet Padding (reflected)                     ~
    +                                               +-+-+-+-+-+-+-+-+
    |                                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

          Figure 5: STAMP Session-Reflector test packet format in
                           unauthenticated mode

   where fields are defined as the following:

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   o  Sequence Number is four octets long field.  The value of the
      Sequence Number field is set according to the mode of the STAMP
      Session-Reflector:

      *  in the stateless mode the Session-Reflector copies the value
         from the received STAMP test packet's Sequence Number field;

      *  in the stateful mode the Session-Reflector counts the received
         STAMP test packets in each test session and uses that counter
         to set the value of the Sequence Number field.

   o  Timestamp and Receiver Timestamp fields are each eight octets
      long.  The format of these fields, NTP or PTPv2, indicated by the
      Z flag of the Error Estimate field as described in Section 4.1.

   o  Error Estimate has the same size and interpretation as described
      in Section 4.1.

   o  Session-Sender Sequence Number, Session-Sender Timestamp, and
      Session-Sender Error Estimate are copies of the corresponding
      fields in the STAMP test packet sent by the Session-Sender.

   o  Session-Sender TTL is one octet long field, and its value is the
      copy of the TTL field in IPv4 (or Hop Limit in IPv6) from the
      received STAMP test packet.

   o  Packet Padding (reflected) is an optional variable length field.
      The length of the Packet Padding (reflected) field MUST be equal
      to the value of the Server Octets field (Figure 2).  If the value
      is non-zero, the Session-Reflector MUST copy number of octets
      equal to the value of Server Octets field starting with the Server
      Octets field.

   o  Comp.MBZ is a variable length field used to achieve alignment on a
      word boundary.  Thus the length of Comp.MBZ field may be only 0,
      1, 2 or 3 octets.  The value of the field MUST be zeroed on
      transmission and ignored on receipt.

4.2.2.  Session-Reflector Packet Format in Authenticated Mode

   For the authenticated mode:

      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)                        |

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      |                                                               |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                          Timestamp                            |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         Error Estimate        |                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
      |                        MBZ (6 octets)                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Receive Timestamp                      |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        MBZ (8 octets)                         |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                 Session-Sender Sequence Number                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        MBZ (12 octets)                        |
      |                                                               |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                 Session-Sender Timestamp                      |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | Session-Sender Error Estimate |                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
      |                        MBZ (6 octets)                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |Ses-Sender TTL |                                               |
      +-+-+-+-+-+-+-+-+                                               +
      |                                                               |
      |                        MBZ (15 octets)                        |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        HMAC (16 octets)                       |
      |                                                               |
      |                                                               |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure 6: STAMP Session-Reflector test packet format in authenticated
                                   mode

   The field definitions are the same as the unauthenticated mode,
   listed in Section 4.2.1.  Additionally, the packet MAY include
   Comp.MBZ field is a variable length field to align the packet on 16

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   octets boundary.  Also, STAMP Session-Reflector test packet format in
   authenticated mode includes a key (HMAC) ([RFC2104]) hash at the end
   of the PDU.  The detailed use of the HMAC field is in Section 4.3.

4.3.  Integrity and Confidentiality Protection in STAMP

   To provide integrity protection, each STAMP message is being
   authenticated by adding Hashed Message Authentication Code (HMAC).
   STAMP uses HMAC-SHA-256 truncated to 128 bits (similarly to the use
   of it in IPSec defined in [RFC4868]); hence the length of the HMAC
   field is 16 octets.  HMAC uses own key and the definition of the
   mechanism to distribute the HMAC key is outside the scope of this
   specification.  One example is to use an orchestrator to configure
   HMAC key based on STAMP YANG data model [I-D.ietf-ippm-stamp-yang].
   HMAC MUST be verified as early as possible to avoid using or
   propagating corrupted data.

   If confidentiality protection for STAMP is required, encryption at
   the higher level MUST be used.  For example, STAMP packets could be
   transmitted in the dedicated IPsec tunnel or share the IPsec tunnel
   with the monitored flow.

4.4.  Interoperability with TWAMP Light

   One of the essential requirements to STAMP is the ability to
   interwork with a TWAMP Light device.  There are two possible
   combinations for such use case:

   o  STAMP Session-Sender with TWAMP Light Session-Reflector;

   o  TWAMP Light Session-Sender with STAMP Session-Reflector.

   In the former case, the Session-Sender MAY not be aware that its
   Session-Reflector does not support STAMP.  For example, a TWAMP Light
   Session-Reflector may not support the use of UDP port 862 as defined
   in [RFC8545].  Thus STAMP Session-Sender MUST be able to send test
   packets to destination UDP port number from the Dynamic and/or
   Private Ports range 49152-65535, test management system should find a
   port number that both devices can use.  And if any of STAMP
   extensions are used, the TWAMP Light Session-Reflector will view them
   as Packet Padding field.  The Session-Sender SHOULD use the default
   format for its timestamps - NTP.  And it MAY use PTPv2 timestamp
   format.

   In the latter scenario, the test management system should set STAMP
   Session-Reflector to use UDP port number from the Dynamic and/or
   Private Ports range.  As for Packet Padding field that the TWAMP
   Light Session-Sender includes in its transmitted packet, the STAMP

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   Session-Reflector will process it according to [RFC6038] and return
   reflected packet of the symmetrical size.  The Session-Reflector MUST
   use the default format for its timestamps - NTP.

5.  IANA Considerations

   This document doesn't have any IANA action.  This section may be
   removed before the publication.

6.  Security Considerations

   In general, all the security considerations related to TWAMP-Test,
   discussed in [RFC5357] apply to STAMP.  Since STAMP uses the well-
   known UDP port number allocated for the OWAMP-Test/TWAMP-Test
   Receiver port, the security considerations and measures to mitigate
   the risk of the attack using the registered port number documented in
   Section 6 [RFC8545] equally apply to STAMP.  Because of the control
   and management of a STAMP test being outside the scope of this
   specification only the more general requirement is set:

      To mitigate the possible attack vector, the control and management
      of a STAMP test session MUST use the secured transport.

   Use of HMAC-SHA-256 in the authenticated mode protects the data
   integrity of the STAMP test packets.

7.  Acknowledgments

   Authors express their appreciation to Jose Ignacio Alvarez-Hamelin
   and Brian Weis for their great insights into the security and
   identity protection, and the most helpful and practical suggestions.
   Also, our sincere thanks to David Ball for his thorough review and
   helpful comments.

8.  References

8.1.  Normative References

   [IEEE.1588.2008]
              "Standard for a Precision Clock Synchronization Protocol
              for Networked Measurement and Control Systems",
              IEEE Standard 1588, March 2008.

   [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>.

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   [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>.

   [RFC5905]  Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch,
              "Network Time Protocol Version 4: Protocol and Algorithms
              Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010,
              <https://www.rfc-editor.org/info/rfc5905>.

   [RFC6038]  Morton, A. and L. Ciavattone, "Two-Way Active Measurement
              Protocol (TWAMP) Reflect Octets and Symmetrical Size
              Features", RFC 6038, DOI 10.17487/RFC6038, October 2010,
              <https://www.rfc-editor.org/info/rfc6038>.

   [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>.

   [RFC8186]  Mirsky, G. and I. Meilik, "Support of the IEEE 1588
              Timestamp Format in a Two-Way Active Measurement Protocol
              (TWAMP)", RFC 8186, DOI 10.17487/RFC8186, June 2017,
              <https://www.rfc-editor.org/info/rfc8186>.

   [RFC8545]  Morton, A., Ed. and G. Mirsky, Ed., "Well-Known Port
              Assignments for the One-Way Active Measurement Protocol
              (OWAMP) and the Two-Way Active Measurement Protocol
              (TWAMP)", RFC 8545, DOI 10.17487/RFC8545, March 2019,
              <https://www.rfc-editor.org/info/rfc8545>.

8.2.  Informative References

   [BBF.TR-390]
              "Performance Measurement from IP Edge to Customer
              Equipment using TWAMP Light", BBF TR-390, May 2017.

   [I-D.ietf-ippm-stamp-yang]
              Mirsky, G., Xiao, M., and W. Luo, "Simple Two-way Active
              Measurement Protocol (STAMP) Data Model", draft-ietf-ippm-
              stamp-yang-03 (work in progress), March 2019.

Mirsky, et al.          Expires October 25, 2019               [Page 13]
Internet-Draft                    STAMP                       April 2019

   [RFC2104]  Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed-
              Hashing for Message Authentication", RFC 2104,
              DOI 10.17487/RFC2104, February 1997,
              <https://www.rfc-editor.org/info/rfc2104>.

   [RFC4868]  Kelly, S. and S. Frankel, "Using HMAC-SHA-256, HMAC-SHA-
              384, and HMAC-SHA-512 with IPsec", RFC 4868,
              DOI 10.17487/RFC4868, May 2007,
              <https://www.rfc-editor.org/info/rfc4868>.

Authors' Addresses

   Greg Mirsky
   ZTE Corp.

   Email: gregimirsky@gmail.com

   Guo Jun
   ZTE Corporation
   68# Zijinghua Road
   Nanjing, Jiangsu  210012
   P.R.China

   Phone: +86 18105183663
   Email: guo.jun2@zte.com.cn

   Henrik Nydell
   Accedian Networks

   Email: hnydell@accedian.com

   Richard Foote
   Nokia

   Email: footer.foote@nokia.com

Mirsky, et al.          Expires October 25, 2019               [Page 14]