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RE: Last Call: CR-LDP Extensions for ASON to Informational

2003-01-24 08:42:11
Hi Gerry,

In your email, below, you indicate that "What was not well communicated is the 
the ITU decided (recently) to do the GMPLS/ASON extnesions themselves.  I think 
many of the postings on this thread indicate that people were not aware of,
and disagree with, this approach".

Quoting from an earlier message from Steve Trowbridge (see below), you can see 
that proposed extensions were communicated
to ccamp via a May 10, 2002 liaison, and presented at the following Yokohama 
IETF meeting.  This was subsequent to the Feb. 19, 2001 liaison identifying the 
gaps that had been identified and requesting support.

 "On February 19, 2002, ITU-T sent IETF ccamp a liaison statement regarding
  the gaps that had been identified between the ITU-T requirements (sent
  earlier) and what seemed to be implemented by the GMPLS protocols. 
Specifically,
  1. Call & Connection separation, e.g., a call provides the service
     relationship, which may support connection operations as part of a call. 
  2. Additional error codes/values, for example, for connection rejection
     (invalid connection ID). 
  3. Restart mechanisms: Depending on the introduction by the ITU of additional
     control plane resiliency requirements, enhancements of the protocol
     (RSVP-TE, CR-LDP) "graceful restart" mechanisms may be required. 
  4. Protocol enhancements in CR-LDP for support of crankback capability from
     intermediate nodes. 
  This liaison was presented in the Minneapolis IETF meeting during the ccamp
  working group and posted on the IESG web site. The liaison requested
  assistance in closing these gaps and invited input from IETF on our work
  in ITU-T.
- At the April/May 2002 meeting of ITU-T Study Group 15 meeting, contributions
  were considered to close these gaps, resulting in text for draft 
Recommendations
  G.7713.2 (our rsvp-te document) and G.7713.3 (our cr-ldp document). Again,
  we sent a liaison (dated May 10, 2002) to ask for comments on our draft
  Recommendations (made available on the ftp site), to request alignment, and
  to ask for IANA code point assignments. To quote from that liaison:
"Please consider including the proposed solutions provided in G.7713.2 and 
G.7713.3
to update the existing GMPLS signaling work in support of ASON requirements.
We hope that you can help expedite the assignment of appropriate additional
error codes/values by IANA.  These are needed for both RSVP-TE and CR-LDP."
  This liaison was presented at the Yokohama IETF ccamp meeting."

Best regards,
Eve

-----Original Message-----
From: Ash, Gerald R (Jerry), ALABS [mailto:gash(_at_)att(_dot_)com]
Sent: Friday, January 24, 2003 9:28 AM
To: Lin, Zhi-Wei (Zhi); iesg(_at_)ietf(_dot_)org; ietf(_at_)ietf(_dot_)org
Cc: Ash, Gerald R (Jerry), ALABS; Stephen Trowbridge; David Charlap; Loa
Andersson; Wijnen, Bert (Bert)
Subject: RE: Last Call: CR-LDP Extensions for ASON to Informational


Zhi,

I have followed the ASON and CCAMP work quite closely over the last couple of 
years.  I am quite familiar and mostly in agreement with your summary of events 
below.  

What was not well communicated is that the ITU decided (recently) to do the 
GMPLS/ASON extensions themselves.  I think many of the postings on this thread 
indicate that people were not aware of, and disagree with, this approach.

I can understand the frustration of not getting attention to the needed ASON 
requirements in IETF/CCAMP.  IETF/CCAMP had been saying (quoting statements 
made by chairs and ADs) they need to 'close the gaps' to meet ASON requirements 
as far back as IETF-53/Minneapolis (March).  CCAMP charter extensions to 
address same were suggested(IETF-54/Yokohama CCAMP meeting minutes say "The 
charter update is way overdue. Items may be added - protection/restoration, 
crankback and multi-area operations."), but CCAMP charter extensions are still 
pending even to this day.  

However, the answer is not for the ITU (or any other standards body) to extend 
IETF protocols, and visa versa.  This leads to interoperability problems, I 
believe, wherein we have 'ITU-TLVs', 'IETF-TLVs', 'OIF-TLVs', etc. for GMPLS 
protocols.  Furthermore, we are now inheriting many 'ITU-TLVs' for RSVP-TE and 
CRLDP.  This precludes, or at least inhibits, proper technical discussion to 
arrive at the best technical approach.  Further discussion on 'ITU-TLVs' (e.g., 
call control, crankback, etc.) is now moot.

Perhaps we can learn from this and improve the process, e.g.:

a) Bert has proposed a (G)MPLS change process (seems like a good idea),
b) better communication and responsiveness, especially from WG chairs on direct 
queries (e.g., 'where is the CCAMP charter update?' has been asked many times, 
but there is no response, still pending).

Regards,
Jerry

-----Original Message-----
From: Lin, Zhi-Wei (Zhi) [mailto:zwlin(_at_)lucent(_dot_)com]
Sent: Friday, January 24, 2003 2:57 AM
To: Ash, Gerald R (Jerry), ALABS; iesg(_at_)ietf(_dot_)org; 
ietf(_at_)ietf(_dot_)org
Cc: Stephen Trowbridge; David Charlap; Loa Andersson
Subject: RE: Last Call: CR-LDP Extensions for ASON to Informational

Hi Jerry,

I'm not sure how long you've followed the entire GMPLS and 
ASON work, but I'm assuming here that you weren't part of the 
original discussions over the last 1.5 to 2 years on this 
matter. That's understandable as this wasn't your original 
area of interest.

However, if you talk with some folks involved since the 
beginning, you would realize (and also reading Steve's email 
on the history, or simply going back to the email archives in 
both MPLS and CCAMP) that
(a) ITU-T tried to get the work done in IETF (I believe Steve 
mentioned Oct. 21, 2001)
(b) IETF never actually started/initiated work to fill these 
gaps. So a set of individuals who happens to attend IETF, OIF 
and ITU decided that they would work towards a solution
(c) This solution was submitted into IETF, OIF, and ITU -- 
with clear intention of trying to get feedback from the 
"true" RSVP experts
(d) I (and Bala) created I-Ds in IETF (Bala actually started 
this I think sometime in early 2002? -- Bala you can confirm 
or correct -- while I submitted my I-D in June 2002)
(e) These documents were never taken seriously (This is the 
first email I sent: 
http://ops.ietf.org/lists/ccamp/ccamp.2002/msg00918.html -- 
but of course no one responded)
(f) ITU-T requests which were publicly presented in CCAMP 
meetings by Wesam and Steve (see Steve's email to see how 
many requests were made) were never taken seriously

The ITU-T delayed their process by several months in order 
for RSVP experts (I guess Bob Braden would call folks who's 
done this work "non-RSVP experts") to review. Of course no 
comments were ever provided by the "true" RSVP experts.

Several individuals tried very hard to try and get a good 
relationship and collaboration going amongst the three 
organizations. The break-down is not for lack of trying or 
exposing the work to the RSVP experts.

As such, although I agree that the original intent of all the 
individuals who came into this work expecting to collaborate 
and do the work in IETF CCAMP WG, the actual situation is 
very much different, and is a result of certain members of 
the CCAMP WG community deciding not to bother with paying 
attention to the work. Again I can understand the perception 
that you get since you weren't involved from the beginning. 
But a casual perusal of the email archives (too much work for 
me, if you're interested you should take a look at the 
history first) would give you a much better and accurate 
history of the discussions (see 
http://ops.ietf.org/lists/ccamp for the CCAMP email archive, 
and 
http://cell.onecall.net/cell-relay/archives/mpls/mpls.index.html 
for the MPLS email archive).

Thanks
Zhi



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