Re: WG LC: draft-ietf-l3vpn-2547bis-mcast-bgp

[Yakov Rekhter <[e-mail]>]

Maria,

[small correction to my previous reply...]

> Comments on section 13.2:
> 
>   "When as a result of receiving a new Source Active A-D route a PE
>    updates its VRF with the route, the PE MUST check if the newly
>    received route matches any <C-*, C-G> entries. If (a) there is a
>    matching entry, (b) the PE does not have (C-S, C-G) state in its
>    MVPN-TIB for (C-S, C-G) carried in the route, and (c) the received
>    route is selected as the best(using the BGP route selection
>    procedures), then the PE sets up its forwarding path to receive (C-S,
>    C-G) traffic from the tunnel the originator of the selected Source
>    Active A-D route uses for sending (C-S, C-G)."
> 
> The condition (b) above excludes the following case: a PE that received
> a Source Active A-D route for (C-S,C-G) has both (C-*, C-G) and (C-S,
> C-G) states in its MVPN-TIB (because its locally attached site switched
> to SPT for C-S). If this PE does not join the tunnel used for C-S
> traffic, this PE will not receive the C-S traffic.
> 
> Also, the section 13.2 has no procedure for the case when a PE that
> received a Source Active A-D route for (C-S,C-G) has the (C-S,C-G) state
> but not the (C-*, C-G) state in its MVPN-FIB. This could be the case,
> for example, when the PE is attached to (a site with) C-RP but it is not
> directly attached to any (C-*, C-G) receiver sites, except those behind
> the C-RP. This PE will also have to join the tunnel used for C-S traffic
> to deliver traffic to those receivers.

The current spec allows (C-S, C-G) to be carried either on I-PMSI or S-PMSI. 

When (C-S, C-G) is carried on I-PMSI the PE joins the tunnel(s) used by
I-PMSI at provisioning time, and therefore does not need to join
any I-PMSI tunnel(s) when it receives a Source Active A-D route.

When (C-S, C-G) is carried over an S-PMSI text in 12.3 covers the issue
of joining the tunnel.

So, the current spec already addresses your comment wrt joining
the tunnel.

Yakov.

> 
> 
> Maria
> 
> > -----Original Message-----
> > From: [e-mail] [mailto:[e-mail]] On Behalf
> > Of Danny McPherson
> > Sent: Friday, November 21, 2008 8:52 AM
> > To: [e-mail]
> > Subject: WG LC: draft-ietf-l3vpn-2547bis-mcast-bgp
> > 
> > 
> > Please consider today the start of a 2-week last call
> > for draft-ietf-l3vpn-2547bis-mcast-bgp, available here:
> > 
> > http://tools.ietf.org/html/draft-ietf-l3vpn-2547bis-mcast-bgp-05
> > 
> > Input on this draft's suitability for publication as an
> > Internet Standards Track document is solicited, feedback
> > ends December 9, 2008.
> > 
> > Thanks in advance for your feedback!
> > 
> > Danny & Marshall
>