The MPLS WG Archive

[Shahram Davari <Shahram_Davari@pmc-sierra.com>]

Hi,

We don't restrict the implementations. Both could be done. However, if the tunneled packet belongs to a Diffserv signaled E-LSP, since we signal the EXP<=>PHB mapping, it might be difficult to do the first option that you mentioned.

Regards,
-Shahram

> -----Original Message-----
> From: Francis Arts [mailto:francis.arts@alcatel.be]
> Sent: Saturday, November 25, 2000 4:30 AM
> To: mpls@UU.NET
> Subject: draft-ietf-mpls-diff-ext-07.txt
> 
> 
> 
> Hello,
> 
> I have a question concerning the 
> draft-ietf-mpls-diff-ext-07.txt draft.
> 
> Section 2.6.2, p.13 of this draft states the following:
> 
> "The Pipe Model is particularly appropriate to environments in which
> the incoming interface of the LSP Ingress and the outgoing interface
> of the LSP Egress are in Diff-Serv domains which use a common set of
> Diff-Serv service provisioning policies and PHB definitions, while
> the LSP spans one (or more) Diff-Serv domain(s) which use(s) a
> different set of Diff-Serv service provisioning policies and PHB
> definitions."
> 
> 
> This statement could be interpreted in 2 ways. Which one is correct:
> 
> 1) The 2 diff serv domains connected by the LSP use the same PHBs but
> may use a different DSCP encoding of the PHB. If a different DSCP
> encoding is used, a translation needs to be done at either end.
> 
> 2) The 2 diff serv domains connected by the LSP use the same PHBs and
> the same
> DSCP encoding of the PHB.
> 
> 
> 
> Thanks for your answer.
> 
> Kind regards,
> 
>     Francis.
>