Liaison statement
ASON Routing in the IETF

Submission date 2009-08-30
From IETF Routing Area (Adrian Farrel)
To ITU-T SG15 Q14 (Greg Jones)
Cc Kam Lam, Stephen Trowbridge, Patrik Fältström, Ross Callon, Deborah Brungard, Lou Berger, CCAMP Working Group
Response contact Adrian Farrel
Technical contact Deborah Brungard, Lou Berger
Purpose For information
Attachments (None)
Dear Mr. Lam,

May I take this opportunity to inform you and Question 14 of Study
Group 15 of the progress of work within the IETF on ASON routing.

_Requirements and Analysis_

As you are aware, the IETF has published two Request For Comment
documents (RFCs) documenting the requirements for GMPLS routing for
ASONs, and an evaluation of existing routing protocols against the ASON
routing requirements. These are:

- RFC 4258 "Requirements for Generalized MPLS (GMPLS) Routing for 
  Automatically Switched Optical Network (ASON),"

- RFC 4652 "Evaluation of existing Routing Protocols against ASON

They are available for free download from

_Inclusion of Additional Requirements_

After repeated approaches from Study Group 15 saying that certain key
routing requirements had been left out of RFC 4258 and that other
requirements had been misrepresented, the IETF held an ad hoc
face-to-face meeting during the 71st IETF in Philadelphia during the
week of 10th March 2008. We discussed the content of the liaison and
focussed in on the major points raised. We were helped in our analysis
by experts from Q14/15 who traveled to form part of the group.

The conclusion of the meeting was that it might be beneficial to revise
RFC 4258 to be sure that it covers all of the requirements in the
latest versions of the ITU-T Recommendations. To achieve this work, a
design team was set up using three volunteers who were active in Study
Group 15 and the Optical Interworking Forum and who were familiar with
the content of G.7715 and G.7715.1. The team was chartered, and a
mailing list was set up to allow open discussion of the issues.

Unfortunately, the design team has been unable to deliver on its
charter. A first version of a draft was posted in October 2008, but no
further progress has been made.

You are informed, therefore, that it is our intention to close this
design team and shut the mailing list.

The IETF welcomes further input on this topic which should be made in
the form of Internet-Drafts with discussion on the mailing list of the
CCAMP working group (

_Protocol Extensions to OSPF_

The IETF's CCAMP working group produced initial work on protocol
extensions to the OSPF routing protocol in support of ASON routing
requirements. In order to facilitate the free work of the design team
described above, CCAMP's work on OSPF was put on hold until the design
team delivered on its charter.

In the light of the failure of the lack of progress revising RFC 4258,
it is not reasonable to hold up the work on OSPF any further.
Consequently, an Internet-Draft ("OSPFv2 Routing Protocols Extensions
for ASON Routing") has been advanced and approved by the IESG. This
will be processed for publication as an RFC. Until the RFC Editor
completes his tasks, the text of this work can be downloaded from:

The RFC will be published on the Experimental track. The IETF considers
that significant modifications to Internet routing protocols need to be
treated with great caution, and that the ASON routing extensions need
to be the subject of experimentation in "walled gardens" in order to
determine the stability of the protocol extensions before they are
released for general use in the Internet.

The IETF would welcome all reports of implementation, interoperability,
and deployment experience of these protocol extensions. All comments
should be sent to the CCAMP working group mailing list.

Best Regards,
Adrian Farrel
IETF Routing Area Director
Liaison to SG15 on the Optical Control Plane