Re: [CCAMP] Working group lastcall:draft-ietf-ccamp-gmpls-vcat-lcas-08

["Evelyne Roch" <[e-mail]>]

Greg, 
 
There is a problem in the architecture because the CALL_ATTRIBUTES is
carrying group info in the member call, creating a dependency on the
members to achieve VCAT signaling. That dependency is problematic in a
network with administrative boundaries.
 
Evelyne

________________________________

From: Greg Bernstein [mailto:[e-mail]] 
Sent: Thursday, December 10, 2009 1:29 PM
To: Roch, Evelyne (CAR:Q840)
Cc: BRUNGARD, DEBORAH A (ATTLABS); CCAMP
Subject: Re: [CCAMP] Working group
lastcall:draft-ietf-ccamp-gmpls-vcat-lcas-08


Hi Evelyne, version 04 published in February of 2008 contained a
"Call_Data_Object", with a TLV containing exactly the information and
utilizing the same procedures that we are now using with the
CALL_ATTRIBUTES object. 
It was recommended by the WG chairs to use the CALL_ATTRIBUTES object as
defined in the MLN-Extensions work rather than defining another
"Call_data_object". None of of the procedures were changed from 04. 
Is there a problem with functionality? We worked very hard to find a
technique utilizing existing mechanisms to give some support forthe
member sharing scenario. We do not preclude other techniques being used
in the future.

Greg

Evelyne Roch wrote: 

	This liaison was referring to version 04, before the
introduction of CALL_ATTRIBUTES in the draft, exactly where the problem
is.
	 
	In the laison 429, the ITU-T agrees to one call per VCG. That is
the VCAT call (not addressed in the draft right now).
	 
	As far as member calls, members could be in same or different
calls based on application (for diverse routing -> could be same call,
for protection/restoration -> could be different calls). That is the
member call used in the draft. 
	 
	The problem is that CALL_ATTRIBUTES is carried in member call
signaling when it pertains to the VCG, i.e. VCAT call. 
	 
	Evelyne
	 
	 
	 
	 

________________________________

	From: Greg Bernstein [mailto:[e-mail]] 
	Sent: Thursday, December 10, 2009 11:16 AM
	To: Roch, Evelyne (CAR:Q840)
	Cc: BRUNGARD, DEBORAH A (ATTLABS); CCAMP
	Subject: Re: [CCAMP] Working group
lastcall:draft-ietf-ccamp-gmpls-vcat-lcas-08
	
	
	Hi Evelyne, I'll add some text to the requirements section to
clarify "common pool" per your request.
	The "call concept" usage and "member sharing scenario" have been
previously discussed, liaised, and resolved with ITU-T. 
	
	https://datatracker.ietf.org/liaison/415/
	
	It includes:
	ITU: "Per Question 5:  We understand that this draft is only
addressing
	the
	constituent server layer call; i.e., not the ASON multilayer
call
	supporting call construct. However, we suggest that you do not
preclude
	extensions to use a call in the VCAT layer.
	
	CCAMP response: As noted above, this is not precluded. We look
forward to
	future communication from you as you progress this work."
	
	Q14 later responded saying they were satisfied with the one call
	construct:
	https://datatracker.ietf.org/liaison/429/
	Greg
	
	Evelyne Roch wrote: 

		Greg,
		 
		Normally, I would expect the requirements section to be
clear enough that it helps define a proper solution mechanism and
clearly sets the scope, not the other way around (i.e. you need to read
the mechanism to understand how the requirements should be interpreted).
		 
		My main concern is how the "call concept" is being used
with the member sharing scenario, as I mentioned earlier in this thread.
The calls (in the draft) are really member calls, not VCAT group calls.
But the call attributes contain VCAT group information. I don't want the
member call to attribute carry call information for the entire VCAT
group.
		 
		Evelyne

________________________________

		From: Greg Bernstein
[mailto:[e-mail]] 
		Sent: Wednesday, December 09, 2009 5:34 PM
		To: Roch, Evelyne (CAR:Q840)
		Cc: BRUNGARD, DEBORAH A (ATTLABS); CCAMP
		Subject: Re: [CCAMP] Working group
lastcall:draft-ietf-ccamp-gmpls-vcat-lcas-08
		
		
		Hi Evelyne, the common pool is a set of potential member
signals that have been set up using the mechanisms defined in the draft,
particularly the VCAT call procedures. The draft allows these to be
"shared" amongst different VCGs over time. Note that at any given point
in time a member signal can belong to only one VCG. Note that by the
nature of VCAT that these are signals that have the same source and
destination. The procedures section makes this fairly clear.
		
		Greg
		
		
		
		Evelyne Roch wrote: 

			Greg,
			 
			First, I think we need to further clarify the
requirements as I'm not sure all the readers will interpret the
requirements the same way. What exactly does it mean to be "in a common
pool"?
			 
			Evelyne

________________________________

			From: Greg Bernstein
[mailto:[e-mail]] 
			Sent: Tuesday, December 08, 2009 1:04 PM
			To: Roch, Evelyne (CAR:Q840)
			Cc: BRUNGARD, DEBORAH A (ATTLABS); CCAMP
			Subject: Re: [CCAMP] Working group
lastcall:draft-ietf-ccamp-gmpls-vcat-lcas-08
			
			
			Hi Evelyne, the main focus on this work was to
support VCGs with diversely routed routed members. We were asked to
include the member sharing scenario and formulated a method to
accommodate it without significantly increasing the complexity of the
messages involved.  It seems to us that the solution included in this
draft provides sufficient functionality to meet the requirements in the
document. Is there a scenario you think is within the scope of the draft
that is not addressed?
			
			Greg
			
			Evelyne Roch wrote: 

				Greg, see below.
				
				  

				-----Original Message-----
				From: Greg Bernstein
[mailto:[e-mail]] 
				Sent: Friday, December 04, 2009 4:09 PM
				To: Roch, Evelyne (CAR:Q840)
				Cc: BRUNGARD, DEBORAH A (ATTLABS); CCAMP
				Subject: Re: [CCAMP] Working group
				    

	
lastcall:draft-ietf-ccamp-gmpls-vcat-lcas-08
				
				<snip>
				
				  

				I'm not sure that we have calls of calls
in GMPLS. At the time this
				was written this wasn't deemed
desirable.
				    

				
				The model of calls being supported by
calls is clearly support by ASON,
				whether at the same layer (see G.8080
section 6.7) or different layer
				(section 6.6). I find it highly
desirable.
				
				<snip>
				
				Evelyne
				
				
				  


			-- 
	
===================================================
			Dr Greg Bernstein, Grotto Networking (510)
573-2237
			
			  


		-- 
		===================================================
		Dr Greg Bernstein, Grotto Networking [phone]
		
		  


	-- 
	===================================================
	Dr Greg Bernstein, Grotto Networking [phone]
	
	  


-- 
===================================================
Dr Greg Bernstein, Grotto Networking [phone]