Re: draft-ietf-mpls-rsvp-te-p2mp-06.txt [P2MP ID]

[Yakov Rekhter <yakov@juniper.net>]

Lou,

> >[clipped...]
> >
> > > > > > > >    The P2MP ID provides an identifier for the set of
> > > > > > > >    destinations of the P2MP TE Tunnel.
> > > > > > > >
> > > > > > > >The last sentence above has to be deleted.
> > > > > > >
> > > > > > > why, what's incorrect about it?
> > > > > >
> > > > > >To begin with, the last sentence states that the P2MP ID, *by itself*
> > > > > >"provides an identifier for the set of destinations of a given P2MP
> > > > > >TE Tunnel". However, since a given P2MP ID, *by itself*, may not
> > > > > >be unique, how could it unambiguously identify the set of 
> > > > > >destinations of such tunnel ?
> > > > >
> > > > > You are 100% correct, how about fixing it by saying:
> > > > > "The P2MP ID together with Tunnel ID, Extended Tunnel ID provide an
> > > > > identifier for the set of destinations of the P2MP TE Tunnel."
> > > >
> > > >Given that P2MP ID is unique within the scope of the root, why a
> > > >tuple <Extended Tunnel ID, P2MP ID> is not sufficient to identify
> > > >the set of destinations of a P2MP tunnel ? After all, you agreed
> > > >further down that such a tuple identifies a P2MP tunnel.
> > >
> > > Because this would preclude the use of tunnel ID to further partition
> > > the session space (as is done today for P2P-TE.)  The tuple I
> > > mentioned included all three.
> >
> >You, yourself agreed that "A combination of this address and P2MP
> >ID provides a globally unique identifier for the P2MP tunnel."
> 
> Well actually my point was: "... the uniqueness of the tuple <P2MP 
> ID, Tunnel ID, Extended Tunnel ID>. "
>
> >Since the set of destinations of a P2MP tunnel is just a part of
> >the tunnel, identifying the tunnel should be sufficient in order
> >to identify the set of destinations.
> 
> right, and all three fields are needed.

Could you please provide *technical* reason(s) that would explain why 
a combination of P2MP ID and Extended Tunnel ID is not sufficient ?

Yakov.