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 Routing
They are available for free download from http://www.ietf.org/rfc.html
_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
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
_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.
IETF Routing Area Director
Liaison to SG15 on the Optical Control Plane