Subject: [mpls] PWE3 and MPLS WG response to G.8110.1 Amendment 1

From: Stewart Bryant <[email-masked]>
Date: Wed, 23 May 2007 14:17:18 +0100

To  ITU SG15
CC ITU SG13

For Action

The IETF PWE3 and MPLS WGs are becoming increasingly concerned at the 
potential impact of the proposed re-engineering of MPLS by ITU SG13 and 
SG15 to make it more suitable as "a transport network" called "T-MPLS".

Input from network operators indicates that the key requirements is the 
transparent carriage of the MPLS network of one party over the MPLS 
network of another party, with the constraint that the MPLS design MUST 
NOT be changed and that the solution MUST be compatible with their 
existing large base of already deployed MPLS networks.

Having studied the requirements liaised by SG15 to the IETF
https://datatracker.ietf.org/public/liaison_detail.cgi?detail_id=287

and considered the key issues noted above, the IETF PWE3 and MPLS WGs 
have formed the view that the essential requirements of operators can be 
satisfied by existing IETF protocols.

We therefore liaise the following standards track internet draft for 
your information and would welcome any comments you have on it. It would 
be useful if your response were available for us to consider at IETF69 
which meets on 22 July 2007.

http://www.ietf.org/internet-drafts/draft-ietf-pwe3-mpls-transport-00.txt

On a more general note please can we draw the attention of ITU SG15 to 
ftp://ftp.rfc-editor.org/in-notes/internet-drafts/draft-andersson-rtg-gmpls-change-08.txt 

Regards

Stewart Bryant
on behalf of
IETF PWE3 and MPLS Co-chairs

_______________________________________________
pwe3 mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/pwe3

_______________________________________________
mpls mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/mpls

---

From: Stewart Bryant <[email-masked]>
Date: Wed, 23 May 2007 14:26:53 +0100

To ITU SG15
CC ITU SG13

For Action

The PWE3 and MPLS WGs have studied ITU SG15 Q12 Liaison Progress on 
G.8110.1
Amendment

https://datatracker.ietf.org/public/liaison_detail.cgi?detail_id=312

and have the following comments on the document:

Section 3.5 Transport MPLS definition

Should be amended to make it clear TMPLS is a true subset of IETF PWE3 
over MPLS and that in the case of any differences, the IETF definition 
is considered the Normative definition.

Section 4.7.2 and A.3

The PWE3 WG is concerned that the OAM is not based on VCCV. Any true
subset of the IETF PWE3/MPLS design should allow the use of the IETF
preferred OAM mechanism. This does not preclude the ITU specifying an
additional mechanism as an optional extension to enhance VCCV, although
it would be preferable for the ITU to work with the IETF to enhance VCCV
to provide the additional OAM mechanisms that are needed.

The PWE3 WG is not clear how you determine that the client signal is not
present when the client is a packet service.

Section 4.10

"– Minimize the rerouting distance (to avoid physical layer impairments
on the signals)."

We do not understand why in a well engineered network the distance in
the virtual layer providing reroute has impact results in physical layer
impairments

Appendix V

The introductory material to Appendix V states that it will be
re-written at some time in the future to align with the IETF work on
p2mp LSPs. We would therefore request that you liaise the final text to 
us when it is completed.

As it stands the text of Appendix V looks correct, however we do have
two proposals that we would ask you consider

1. We recommend that Upstream Assigned Labels be used over P2MP
connections, or at least that you note in the text that generally 
administration of labels is simplified by using upstream assignment in 
this scenario.

2. That you include a reference to RFC 4875 (RSVP-P2MP) as
this discusses many issues pertaining to P2MP MPLS connections.

The PWE3 and MPLS WGs will meet at IETF69 on 22 July 2007, and we would 
request a response in time for us to consider at the meeting.

Regards

Stewart Bryant
on behalf of