[rbridge] per-VLAN instances of IS-IS

[Silvano Gai]

Anoop,

If the language in my email is the problem, I take it back.
I am happy with the language in the draft.

-- Silvano

> -----Original Message-----
> From: Eric Gray (LO/EUS) [mailto:eric.gray at ericsson.com]
> Sent: Wednesday, June 20, 2007 1:22 PM
> To: Radia Perlman; Anoop Ghanwani
> Cc: Silvano Gai; rbridge at postel.org
> Subject: RE: [rbridge] per-VLAN instances of IS-IS
> 
> Radia, et al,
> 
> 	I was not challenging consensus on multi-pathing, for either
> unicast or multicast.  What I was objecting to was the assertion
> that we ONLY do ECMP in "core" RBridges - which Silvano had stated
> as if a WG decision.  Since I seriously doubt that we could ever
> arrive at a consensus as to exactly what sort of real-world device
> would be a "core" RBridge, I don't think we have concluded that we
> ONLY do <anything you choose to talk about> in such a beasty.
> 
> 	See Silvano's original comments toward the very end of this
> (snipped) message.
> 
> Thanks!
> 
> --
> Eric Gray
> Principal Engineer
> Ericsson
> 
> > -----Original Message-----
> > From: Radia Perlman [mailto:Radia.Perlman at sun.com]
> > Sent: Wednesday, June 20, 2007 4:00 PM
> > To: Anoop Ghanwani
> > Cc: Eric Gray (LO/EUS); Silvano Gai; rbridge at postel.org
> > Subject: Re: [rbridge] per-VLAN instances of IS-IS
> >
> > I'm also assuming we are doing multipathing, not just of unicast,
but
> > also multicast.
> >
> > Radia
> >
> >
> > Anoop Ghanwani wrote:
> > > Personally, I would like the group to get to a
> > > consensus on the ECMP issue fairly quickly.
> > >
> > > I too, just like Silvano, thought it was going
> > > to be done.
> > >
> > > Anoop
> > >
> > >
> > >> -----Original Message-----
> > >> From: Eric Gray (LO/EUS) [mailto:eric.gray at ericsson.com]
> > >> Sent: Wednesday, June 20, 2007 7:29 AM
> > >> To: Silvano Gai; Anoop Ghanwani
> > >> Cc: rbridge at postel.org; Radia Perlman
> > >> Subject: RE: [rbridge] per-VLAN instances of IS-IS
> > >>
> > >> Silvano,
> > >>
> > >> 	Yes, that was probably discussed earlier in May.
> > >>
> > >> 	AFAIK, discussion != consensus.
> > >>
> > >> 	Possibly your customers need to explain to you that the
> > >> difference between "core" and "not core" is not always as
> > >> clear cut as you apparently think it is.  Nor is it
> > >> necessarily going to be simple for a device to determine
> > >> which of the available equal cost paths only contain core
elements.
> > >>
> > >> 	Also, ECMP - at least in the traditional sense - takes
> > >> place where equal costs exist in a "routing" domain.  That is
> > >> at least as likely to occur in locii containing one or more
> > >> edge components, as it is anywhere else.
> > >>
> > >> 	There are certainly limited applications - typically
> > >> requiring careful configuration to restrict ECMP-like
> > >> activity to very specifically defined equal cost paths -
> > >> where it will be possible to say "we do ECMP only in the
> > >> core."  I personally wonder why link-bundling wouldn't be a
> > >> better solution in those cases, however.
> > >>
> > >> Thanks!
> > >>
> > >> --
> > >> Eric Gray
> > >> Principal Engineer
> > >> Ericsson
> > >>
> > >>
> > >>> -----Original Message-----
> > >>> From: Silvano Gai [mailto:sgai at nuovasystems.com]
> > >>> Sent: Tuesday, June 19, 2007 11:39 PM
> > >>> To: Eric Gray (LO/EUS); Anoop Ghanwani
> > >>> Cc: rbridge at postel.org; Radia Perlman
> > >>> Subject: RE: [rbridge] per-VLAN instances of IS-IS
> > >>> Importance: High
> > >>>
> > >>> We had this discussion on May 8th, 2007 on this mailing list.
> > >>>
> > >>> In a nutshell: we do ECMP only in the core, but we don't
> > >>>
> > >> learn in the
> > >>
> > >>> core, so I don't see the problem.
> > >>>
> > >>> -- Silvano
> --- SNIP ---