RE: [PWE3] question on draft-mohan-pwe3-vccv-eth-01.txt

["Hamid Ould-Brahim" <[e-mail]>]

Peter, Andy, All,
 
I think we need to be more precise of what we mean by 
"non IP/MPLS PSN". From this discussion it looks to me
that there are two options considered for non IP/MPLS PSN:
 
Option a: 
 
  Carrying Pseudowire over MPLS-in-Foo (with Foo can be
  Ethernet, etc). In this case the PW demultiplexor 
  is always an MPLS label. This is similar to MPLS-in-IP. 
 
Option b:
 
   Carrying Pseudowire over Foo, (Foo= Ethernet, etc).
   In this case the Pseudowire demultiplexor (or even
   the tunneling control protocol) is Foo-based. 
 
I think this discussion is more pointing to option "a"  
which is MPLS-over-Ethernet. Option a is not exactly
a non MPLS type PSN. Note that RFC4447 indicates
that:
 
  "Any sort of PSN tunnel can be used, as long as it is possible 
   to transmit MPLS packets through it.  The PSN tunnel can itself 
   be an MPLS LSP, or any other sort of tunnel that can carry MPLS 
   packets."
 
Since RFC4447 already covers the case of MPLS-in-X type
tunnels, a simple option to consider is to include 
MPLS-in-Ethernet (MPLS-in-Foo in general) type tunnels 
as part of MPLS PSNs. 
 
Add to it that if "MPLS-in-Ethernet" PSN 
is using the encoding already defined in RFC3032 (in other words 
RFC3032 can be interpreted as defining encoding for MPLS-in-X 
type PSNs where X=Ethernet) then this will fit nicely 
with existing pwe3 charter.
 
Hamid.
 



________________________________

	From: Busschbach, Peter B (Peter)
[mailto:[e-mail]] 
	Sent: Monday, March 05, 2007 7:00 PM
	To: Andrew G. Malis
	Cc: Mark Townsley; pwe3; Shah, Himanshu; Stewart Bryant
	Subject: RE: [PWE3] question on draft-mohan-pwe3-vccv-eth-01.txt
	
	
	Andy,
	 
	The charter language does not apply in the case of adjacent PEs.
You can't mandate that there be an MPLS network between adjacent PEs,
because then they would not be adjacent.
	 
	That said, I agree that the text in RFC4447 was not meant to
sanction PWs over Ethernet. We should update the charter and allow PWs
over any packet switched network.
	 
	Peter


________________________________

		From: Andrew G. Malis [mailto:[e-mail]] 
		Sent: Monday, March 05, 2007 6:50 PM
		To: Busschbach, Peter B (Peter)
		Cc: Mark Townsley; pwe3; Shah,Himanshu; Stewart Bryant
		Subject: RE: [PWE3] question on
draft-mohan-pwe3-vccv-eth-01.txt
		
		
		Peter,
		
		Thanks for pointing that out. However, that doesn't
change the existing charter language.
		
		Cheers,
		Andy
		
		-------
		
		At 3/5/2007 05:43 PM -0600, Busschbach, Peter B
\(Peter\) wrote:
		

			Andy,
			 
			I respectfully disagree. The text that I quoted
says "... if the pseudowire endpoints are immediately adjacent ...".
Note the "s" at the end of "endpoints". Therefore, the text is about
adjacent PEs and it says that in that case there is no need for an MPLS
tunnel to carry the PW. In other words, the PW can be carried directly
over the link layer between the adjacent PEs.
			 
			Peter
			
			

________________________________

				From: Andrew G. Malis [
mailto:[e-mail] <mailto:[e-mail]> ] 
				
				Sent: Monday, March 05, 2007 6:33 PM
				
				To: Shah, Himanshu
				
				Cc: Busschbach, Peter B (Peter); Stewart
Bryant; Mark Townsley; pwe3
				
				Subject: RE: [PWE3] question on
draft-mohan-pwe3-vccv-eth-01.txt
				
				
				I would like to point out that the
intent of the RFC 4447 text quoted by Peter was to ONLY allow PHP to be
used on the physical link between the penultimate P router and the PE
router where the PW terminates and connects with the attachment circuit.
In this one case only, the MPLS tunnel used to carry the PW terminates
at the penultimate P router rather than at the PE router. It was not
meant to be a general escape mechanism to allow the general use of PWs
over tunneling mechanisms other than MPLS or L2TPv3. 
				
				
				Further, to quote the WG charter,
				
				
				"Pseudowire Emulation Edge to Edge
(PWE3) will specify the
				
				encapsulation, transport, control,
management, interworking and
				
				security of services emulated over IETF
specified PSNs."
				
				
				Ethernet and SONET are not IETF
specified PSNs.
				
				
				So, while there may be value in
supporting PWs over non-IETF-specified PSNs, I do agree with Stewart and
Mark that a charter change will be necessary to pursue this work.
				
				
				Cheers,
				
				Andy
				
				
				--------
				
				
				
				At 3/5/2007 05:51 PM -0500, Shah,
Himanshu wrote:
				

				Content-class:
urn:content-classes:message
				
				Content-Type: multipart/alternative;
				
	
boundary="----_=_NextPart_001_01C75F78.CAA52CEF"
				
				
				I believe this is a key point.
				
				In my view, discussions on in/out scope
				
				really does not apply (for the reasons
				
				described below). Also, note that as L2
				
				technology becomes more intelligent (eg.
PBT),
				
				keeping it out-of-scope (artificially)
would be
				
				a mistake.
				
				
				There are other docs (past/present),
that already
				
				use this concept, such as dry martini,
				
				MEF3/8 (TDM-PWoETH, except ethType is
different),
				
				pw-over-pbt, etc.
				
				
				IMO,
				
				himanshu
				
				
				
				-----Original Message-----
				
				From: Busschbach, Peter B (Peter) [
mailto:[e-mail]]
				
				Sent: Mon 3/5/2007 5:24 PM
				
				To: Stewart Bryant; Mark Townsley
				
				Cc: pwe3
				
				Subject: RE: [PWE3] question on
draft-mohan-pwe3-vccv-eth-01.txt
				
				
				Dave Allan made a point that I believe
is valid and makes this whole
				
				discussion irrelevant. To rephrase what
he said:
				
				
				Page 4 of RFC 4447 says:
				
				
				   In the protocol specified herein, the
pseudowire demultiplexor field
				
				   is an MPLS label.  Thus, the packets
that are transmitted from one
				
				   end of the pseudowire to the other
are MPLS packets, which must be
				
				   transmitted through an MPLS tunnel.
However, if the pseudowire
				
				   endpoints are immediately adjacent
and penultimate hop popping
				
				   behavior is in use, the MPLS tunnel
may not be necessary. 
				
				
				Based on this logic, PWs can be carried
over SDH, Ethernet or any other
				
				protocol that can carry MPLS packets
without violating the PWE3 charter.
				
				
				Peter
				
				
				
				> -----Original Message-----
				
				> From: Stewart Bryant
[mailto:[e-mail]]
				
				> Sent: Monday, March 05, 2007 1:35 PM
				
				> To: Mark Townsley
				
				> Cc: pwe3
				
				> Subject: Re: [PWE3] question on
draft-mohan-pwe3-vccv-eth-01.txt
				
				>
				
				>
				
				> So the proposal seems to be that PWE3
extends VCCV for use
				
				> with a PWE3 PW over a non IP/MPLS PSN.
				
				>
				
				> We should put this on the agenda for
Prague.
				
				>
				
				> - Stewart
				
				>
				
				>
				
				>
_______________________________________________
				
				> pwe3 mailing list
				
				> [e-mail]
				
				>
https://www1.ietf.org/mailman/listinfo/pwe3
				
				>
				
				
	
_______________________________________________
				
				pwe3 mailing list
				
				[e-mail]
				
	
https://www1.ietf.org/mailman/listinfo/pwe3
				
				
	
_______________________________________________
				
				pwe3 mailing list
				
				[e-mail]
				
	
https://www1.ietf.org/mailman/listinfo/pwe3



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