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Liaison statement
Comments on SG15 OTNT standardization work plan

State Posted
Submitted Date 2011-01-31
From Group RTG
From Contact Adrian Farrel
To Group ITU-T-SG-15
To Contacts Greg Jones <
Cc Adrian Farrel <>
Stewart Bryant <>
The IETF Chair <>
Response Contact Adrian Farrel <>
CCAMP Working Group <>
PCE Working Group <>
MPLS Working Group <>
IETF ITU-T Liaisons <>
Technical Contact Adrian Farrel <>
Purpose In response
Attachments (None)
Liaisons referred by this one LS204 - SG15 OTNT standardization work plan
The IETF thanks you for your liaison COM15-LS204-E received on 2010-06-24 titled
"SG15 OTNT standardization work plan", and thanks you for sharing your plans.

We have reviewed the document and have a number of comments.

In general, it is becoming less and less clear that the title of this document
is accurate! SG15 now embraces a number of non-optical transport technologies
including Ethernet and MPLS-TP. Although those packet-based technologies can be
transmitted over optical links, they are not limited to that medium. Maybe your
document should be titled "Transport Networks & Technologies Standardization
Work Plan" or maybe you should remove the non-optical material. The scope text
in Section 5 and 5.1 might also need revision. The IETF has not position of
this, but simply draws the matter to your attention.

Table 5-1
We would like to suggest the inclusion of the MPLS Working Group in this table
as that working group is responsible for many elements of the support of
Ethernet "carrier-class" pseudowires over MPLS and MPLS-TP networks.

Section 5.6.1 begins: "MPLS OAM was originally standardized by ITU-T SG13
(Q.5/13)." Although the section goes on to list IETF standardization of MPLS
OAM, it may be considered that this first sentence implies that the ITU-T
developed MPLS OAM before any MPLS OAM had been developed within the IETF. This
would, of course, be a misrepresentation. Therefore, we suggest that you change
this first sentence to read: "Within the ITU-T, MPLS OAM was originally
standardized by SG13 (Q.5/13)."

Table 5-3
Architectural Aspects of MPLS-TP
   Add RFC 5921, RFC 5950, RFC 5960
Equipment Functional Characteristics of MPLS-TP
   Add RFC 5960
OAM and Protection Switching of MPLS-TP
   Add RFC 5860
Management Aspects of MPLS
   Add RFC 4221
Management Aspects of MPLS-TP
   Add RFC 5950, RFC 5951
Performance of ATM
   Add RFC 3116
Performance of MPLS
   Add RFC 5695

Table 7-1-2
draft-ietf-mpls-tp-framework is now RFC 5921
draft-ietf-mpls-tp-nm-req is now RFC 5951
draft-ietf-mpls-tp-survive-fwk reached revision -06 and has been approved for
publication as an RFC
draft-ietf-mpls-tp-oam-framework reached revision -10 and has been approved for
publication as an RFC
draft-ietf-mpls-tp-nm-framework is now RFC 5950
draft-ietf-mpls-tp-rosetta-stone has reached revision -03
draft-ietf-mpls-tp-data-plane is now RFC 5960
draft-ietf-mpls-tp-identifiers has reached revision -03
draft-ietf-mpls-tp-ach-tlv is now abandoned
draft-ietf-ccamp-mpls-tp-cp-framework has reached revision -05
Further relevant Internet-Drafts and RFCs can be found at:

Table 7-4-2
draft-ietf-gmpls-ason-routing-ospf is now RFC 5787

Table 7-8 should inherit changes to Table 7-1-2 and be updated according to the
document status available at the IETF working group pages as listed above.

Table 8-1 entry 3. Please be aware of the work on impairment-aware routing in
the CCAMP and PCE working groups. (It may be your intention that this is
covered under entry 5.)

Annex A might usefully refer readers to RFC 4397 and
draft-ietf-mpls-tp-rosetta-stone that provide terminology mapping and have been
jointly developed by IETF and ITU-T experts.

We would welcome it if you shared any future revisions of this work plan with

Adrian Farrel
IETF Liaison to the ITU-T on the Optical Control Plane
Routing Area Director