Network Working Group A. Morton
Internet-Draft AT&T Labs
Updates: 4656 and 5357 (if approved) June 25, 2017
Intended status: Standards Track
Expires: December 27, 2017

OWAMP and TWAMP Well-Known Port Assignments


This memo describes new well-known port assignments for the OWAMP and TWAMP protocols for control and measurement, and clarifies the meaning and composition of these standards track protocol names for the industry.

The memo updates RFC 4656 and RFC 5357, in terms of the UDP well-known port assignments.

Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.

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

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This Internet-Draft will expire on December 27, 2017.

Copyright Notice

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Table of Contents

1. Introduction

The IETF IP Performance Metrics (IPPM) working group first developed the One-Way Active Measurement Protocol, OWAMP, specified in [RFC4656]. Further protocol development to support testing resulted in the Two-Way Active Measurement Protocol, TWAMP, specified in [RFC5357].

Both OWAMP and TWAMP require the implementation of a control and mode negotiation protocol (OWAMP-Control and TWAMP-Control) which employs the reliable transport services of TCP (including security configuration and key derivation). The control protocols arrange for the configuration and management of test sessions using the associated test protocol (OWAMP-Test or TWAMP-Test) on UDP transport.

This memo recognizes the value of assigning a well-known UDP port to the *-Test protocols, and that this goal can easily be arranged through port re-assignments.

2. Scope

The scope of this memo is to re-allocate well-known ports for the UDP Test protocols that compose necessary parts of their respective standards track protocols, OWAMP and TWAMP (along with clarifications of the complete protocol composition).

The memo updates [RFC4656] and [RFC5357], in terms of the UDP well-known port assignments.

3. Definitions

This section defines key terms and clarifies the required composition of the OWAMP and TWAMP standards-track protocols.

OWAMP-Control is the protocol defined in Section 3 of [RFC4656].

OWAMP-Test is the protocol defined in Section 4 of [RFC4656].

OWAMP is described in a direct quote from Section 1.1 of[RFC4656]: "OWAMP actually consists of two inter-related protocols: OWAMP-Control and OWAMP-Test." A similar sentence appears in Section 2 of [RFC4656]. Since the consensus of many dictionary definitions of "consist" is "composed or made up of", implementation of both OWAMP-Control and OWAMP-Test are REQUIRED for standards-track OWAMP for standards-track OWAMP specified in [RFC4656].

TWAMP-Control is the protocol defined in Section 3 of [RFC5357].

TWAMP-Test is the protocol defined in Section 4 of [RFC5357].

TWAMP is described in a direct quote from Section 1.1 of [RFC5357]: "Similar to OWAMP [RFC4656], TWAMP consists of two inter-related protocols: TWAMP-Control and TWAMP-Test." Since the consensus of many dictionary definitions of "consist" is "composed or made up of", implementation of both TWAMP-Control and TWAMP-Test are REQUIRED for standards-track TWAMP specified in [RFC5357].

TWAMP Light is an idea described in Informative Appendix I of [RFC5357], and includes an un-specified control protocol (possibly communicating through non-standard means) combined with the TWAMP-Test protocol. The TWAMP Light idea was relegated to the Appendix because it failed to meet the requirements for IETF protocols (there are no specifications for negotiating this form of operation, and no specifications for mandatory-to-implement security features), as decribed in the references below:

Since the idea of TWAMP Light clearly includes the TWAMP-Test component of TWAMP, it is considered reasonable for future systems to use the TWAMP-Test well-known UDP port (whose re-allocated purpose is requested here). Clearly, the TWAMP Light idea envisions many components and communication capabilities beyond TWAMP-Test (facilitating the security requirements, for example), otherwise the Appendix would be one sentence long (equivocating TWAMP Light with TWAMP-Test).

4. New Well-Known Ports

Originally, both TCP and UDP well-known ports were assigned to the control protocols that are essential components of standards track OWAMP and TWAMP.

Since OWAMP-Control and TWAMP-Control require TCP transport, they cannot make use of the UDP ports which were originally assigned. However, test sessions using OWAMP-Test or TWAMP-Test operate on UDP transport. It may simplify some operations to have a well-known port available for the Test protocols as a default port, and this memo requests re-assignment of the UDP well-known port from the Control protocol to the Test protocol (see the IANA Considerations section).

5. Security Considerations

The security considerations that apply to any active measurement of live paths are relevant here as well. See [RFC4656] and [RFC5357].

When considering privacy of those involved in measurement or those whose traffic is measured, the sensitive information available to potential observers is greatly reduced when using active techniques which are within this scope of work. Passive observations of user traffic for measurement purposes raise many privacy issues. We refer the reader to the security and privacy considerations described in the Large Scale Measurement of Broadband Performance (LMAP) Framework [RFC7594], which covers both active and passive techniques.

6. IANA Considerations

This memo requests that IANA re-allocate UDP ports 861 and 862 as shown below, leaving the TCP port assignments as-is:

Service       Port Protocol Description

owamp-control 861  tcp      OWAMP-Control [RFC4656]

owamp-test    861  udp      OWAMP-Test [RFCXXXX]

twamp-control 862  tcp      Two-way Active Measurement
                            Protocol (TWAMP) Control [RFC5357]

twamp-test    862  udp      Two-way Active Measurement
                            Protocol (TWAMP) Test [RFCXXXX]

where RFCXXXX is this memo when published.

7. Acknowledgements

The author thanks ...

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.
[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.
[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.
[RFC7594] Eardley, P., Morton, A., Bagnulo, M., Burbridge, T., Aitken, P. and A. Akhter, "A Framework for Large-Scale Measurement of Broadband Performance (LMAP)", RFC 7594, DOI 10.17487/RFC7594, September 2015.

8.2. Informative References

[LarsAD] "", April 2008.
[TimDISCUSS] "", July 2008.

Author's Address

Al Morton AT&T Labs 200 Laurel Avenue South Middletown, NJ 07748 USA Phone: +1 732 420 1571 Fax: +1 732 368 1192 EMail: URI: