The MPLS WG Archive

[David Charlap <david.charlap@marconi.com>]

"Feng, Mark" wrote:
> 
> I agree fully. What I was trying to say is, if "sharing" is
> desired, the operator really needs to have some "global" knowledge
> of the tunnel IDs; otherwise, he/she might get a nasty surprise.

Absolutely.  No argument here.

> I agree with this as well:-). My point was, the egress router needs
> to base on some kind of criteria to decide the style. That is
> outside the scope of RSVP. Like you said, if the egress router
> completely ignore the information in the Path messages, the
> product might not be that appealing.

I can think of three situations where the egress router may ignore the
ingress router's choice of style:

1: The egress router's code only supports one style, so everything
   gets that style, regardless of request.

2: Another LSP in the same session is using a different style.

3: The operator configured the switch's local policy to override the
   requested style for the LSP.

If none of these three apply, a switch should observe the requested
style flag, since there is no good reason not to.

-- David