Liaison statement
Continued IETF / SG15 Cooperation on T-MPLS and other MPLS Issues

Submission date 2006-07-03
From IETF CCAMP WG (Adrian Farrel)
To ITU-T SG15 (Greg jones)
Cc Loa Andersson, George Swallow, Deborah Brungard, Ross Callon, Bill Fenner, Stewart Bryant, Danny McPherson, Mark Townsley, IESG, IAB, Steve Trowbridge, Malcolm Betts, Ghani Abbas, Houlin Zhao, Yoichi Maeda, Jari Arkko, Scott Bradner, Scott Brim, CCAMP mailing list, MPLS mailing list, PWE3 mailing list
Response contact Adrian Farrel, Ross Callon
Technical contact Stewart Bryant, Loa Andersson
Purpose For action
Deadline 2006-09-25 Action Taken
Attachments (None)
From: Adrian Farrel (IETF Liaison to SG15, CCAMP WG Chair,
      Loa Andersson (IETF MPLS WG Chair;
      George Swallow (IETF MPLS WG Chair;
      Deborah Brungard  (IETF CCAMP WG Chair,
      Ross Callon (IETF Routing Area Director;
      Bill Fenner (IETF Routing Area Director;
      Stewart Bryant (IETF PWE3 WG Chair;
      Danny McPherson  (IETF PWE3 WG Chair,
      Mark Townsley (IETF Internet Area Director,
To:   ITU-T Study Group 15; Greg Jones  (

CC:   IESG  (
      IAB  (
      Steve Trowbridge  (
      Malcolm Betts  (
      Ghani Abbas  (
      Houlin Zhao  (
      Yoichi Maeda   (
      Jari Arkko (
      Scott Bradner  (
      Scott Brim  (
      CCAMP mailing list (
      MPLS mailing list (
      PWE3 mailing list (

Subject: Continued IETF / SG15 Cooperation on T-MPLS and other MPLS Issues

We would like to thank you for the invitation to allow IETF experts to attend
the recent SG15 Rapporteur’s meeting in Ottawa. We were particularly
interested in contributing to the SG15, Question 12 meeting considering T-MPLS
specifications. We note that multiple IETF experts attended, including Ross
Callon (Routing AD), Loa Andersson (MPLS WG Chair), and Stewart Bryant (PWE3
WG Chair). We also note that this meeting resulted in a very cooperative and
productive discussion, which resulted in significantly improved mutual
understanding of issues as well as substantial detailed discussion. This
included detailed technical discussion as well as detailed text editing. 

During the Rapporteur’s meeting, extensive technical updates were proposed
and agreed to for G.8110.1 (Architecture of Transport MPLS (T-MPLS) Layer
Network ). These discussions identified issues, errors, and omissions in
G.8110.1, and also came up with a significant amount of new text which allows
very substantial improvements to this document. These discussions also
identified areas for further consideration and where additional improvements,
clarifications and/or discussions are warranted, such as the need for
specification of the requirements for T-MPLS, as well as for specification of
the scope of applicability.

We would like to strongly recommend that G.8110.1 not be published in the form
that was consented prior to the Ottawa meeting, and that the substantial
improvements that were agreed in the Ottawa meeting be incorporated in the
text prior to publication. Furthermore, due to the extensive nature of these
important improvements, and due to the existence of some further issues that
warrant additional consideration, we also strongly recommend that time be
allowed for review of the updated document by SG15 and IETF experts, including
an additional round of liaison of this document to the IETF, and particularly
to the MPLS, CCAMP, and PWE3 working groups for further review and comment. 

We are aware that a further Rapporteur's meeting is planned for Sophia
Antipolis in the week commencing 18th September 2006, and we hope that it will
be possible to facilitate attendance by non-ITU IETF experts in order to
continue the excellent cooperative progress made in Ottawa. We request that
any updates made to, or proposed for, the text of G.8110.1 be liaised to the
IETF after the September meeting to allow us to make comments in advance of
the SG15 Plenary in October/November this year.

We would like to thank you and SG15 participants for the very positive
interaction at the Ottawa Rapporteur’s meeting, and we look forward to
continued positive interaction between ITU and IETF experts. 


Adrian Farrel
Loa Andersson
George Swallow
Deborah Brungard
Ross Callon
Bill Fenner
Steward Bryant
Danny McPherson
Mark Townsley