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The Pseudowire (PW) and Virtual Circuit Connectivity Verification (VCCV) Implementation Survey Results
RFC 7079

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: IETF-Announce <>
Cc: RFC Editor <>,
    pwe3 mailing list <>,
    pwe3 chair <>
Subject: Document Action: 'The Pseudowire (PW) & Virtual Circuit Connectivity Verification (VCCV) Implementation Survey Results' to Informational RFC (draft-ietf-pwe3-vccv-impl-survey-results-03.txt)

The IESG has approved the following document:
- 'The Pseudowire (PW) & Virtual Circuit Connectivity Verification (VCCV)
   Implementation Survey Results'
  (draft-ietf-pwe3-vccv-impl-survey-results-03.txt) as Informational RFC

This document is the product of the Pseudowire Emulation Edge to Edge
Working Group.

The IESG contact persons are Stewart Bryant and Adrian Farrel.

A URL of this Internet Draft is:

Ballot Text

Technical Summary

   The IETF PWE3 Working Group has defined many encapsulations of
   various layer 1 and layer 2 service-specific PDUs and circuit data.
   In most of these encapsulations, use of the Pseudowire (PW) Control
   Word is required.  However, there are several encapsulations for
   which the Control Word is optional, and this optionality has been
   seen in practice to possibly introduce interoperability concerns
   between multiple implementations of those encapsulations.  This
   survey of the PW/VCCV user community was conducted to determine
   implementation trends and the possibility of always mandating the
   Control Word.

Working Group Summary

   RFC5085 defines 3 VCCV channel types. These are essentially the mechanisms 
   for transport of the PW associated channel that is used to carry e.g. PW OAM
   messages. In addition, RFC6423 adds a 4th mechanism which uses the GAL. There
   is currently no clear definition of which modes are mandatory and which modes 
   are optional to implement. This has caused concerns by some participants in 
   the operator community that the proliferation of modes causes interoperability
   issues between vendors. As a first step to rationalising the number of modes, 
   the WG conducted a survey to try to quantify which modes are in use today and so 
   determine which ones could be either deprecated, or made optional in a possible 
   future update to RFC5085. This draft contains the results of that survey. Since the
   survey contains useful information pertaining to the current state of PW deployments,
   there was consensus to record the results of the survey in an Informational RFC. 
   Note that the draft spent an extended amount of time in AD review while additional
   editorial help was sought to address the comments from the AD. During this period the
   draft went dormant. Additional editorial help was eventually found, and the draft progressed 
   as it was felt that the survey results contained therein were still relevant. The WG 
   has also been using these results as a basis for on-going work, and it was felt that a
   permanent record of the results is desirable.
   Note that the name of the document that was originally last called by the WG was
   draft-ietf-pwe3-pw-vccv-impl-survey-results, but this was updated to
   draft-ietf-pwe3-vccv-impl-survey-results as a result of a comment from
   the WG.

Document Quality

   The document does not specify any MIB changes or additions which would 
   need review.


   The document shepherd is Matthew Bocci.
   The responsible Area Director is Stewart Bryant.


RFC Editor Note