RE: Another question on draft-ietf-tewg-diff-te-proto-01.txt

["David Allan" <dallan@nortelnetworks.com>]

I'm not spotting the difference between what you are saying and what I am
saying....only potential correction to my statement is that I should have
been more precise and said '"can" carry multiple class types.'
 
rgds
Dave

 -----Original Message-----
From: Francois Le Faucheur [mailto:flefauch@cisco.com]
Sent: Tuesday, July 09, 2002 4:49 AM
To: Allan, David [CAR:NS00:EXCH]
Cc: Nabil Seddigh; te-wg@ops.ietf.org
Subject: RE: Another question on draft-ietf-tewg-diff-te-proto-01.txt


Dave,

At 13:24 08/07/2002 -0400, David Allan wrote:


You mean to support the engineering of individual class types in an E-LSP?
An E-LSP by definition carries mulitple class types....


Not quite.
By definition and E-LSP is CAPABLE of carrying traffic from multiple Traffic
Aggregate. But it is perfectly fine to transport traffic from differnet
Traffic Aggregates on differnet E-LSPs (i.e. one Traffic Aggregate per
E-LSP).

When you do not do DS-TE, you woudl generally transport multiple Traffic
Aggregates over E-LSPs.

When you do DS-TE you would either:
        - use L-LSPs
        - use E-LSPs with traffic from a single Traffic Aggregate
        - use E-LSPs with traffic from multiple Traffic Aggregates BUT you
then have a few constraints (see REQTS draft) such as not being able to
perform separate Constraint Based Routing of each TA on  a given E-LSP.


Cheers

Francois


cheers 
Dave 

> -----Original Message----- 
> From: Nabil Seddigh [mailto:nseddigh@tropicnetworks.com] 
> Sent: Monday, July 08, 2002 12:29 PM 
> To: Allan, David [CAR:NS00:EXCH] 
> Cc: te-wg@ops.ietf.org 
> Subject: Re: Another question on draft-ietf-tewg-diff-te-proto-01.txt 
> 
> 
> 
> Dave, 
> 
> Mechanisms to support multiple class types on an E-LSP were proposed 
> in this WG. Some providers and vendors expressed interest in 
> such schemes. However, in Utah, the WG felt that standardizing 
> multiple OA-ELSP would be premature until the basic DS-TE 
> mechanisms are standardized and shown to be viably deployable. 
> 
> Updated versions of the related drafts can be found below: 
> 
> http://www.ietf.org/internet-drafts/draft-ganti-tewg-diffserv- 
> multicos-elspreq-00.txt 
> http://www.ietf.org/internet-drafts/draft-ganti-mpls-diffserv- 
> elsp-02.txt 
> 
> Best, 
> Nabil Seddigh 
> 
> 
> 
> > This implies a 1:1 relationship between TTs and LSPs, this wouldn't 
> > necessarily be true for an E-LSP. Now the mechanisms don't 
> currently exist 
> > to support associating multiple class types/bandwidth 
> constraints for an 
> > E-LSP, but if traffic trunk is exclusively an L-LSP 
> concept, couldn't we pin 
> > this down a bit more explicitly..? 
> > 
> > thanks 
> > Dave 
>