[j-nsp] P2MP LSP

[David water]

All,

I have been trying to understand the P2MP LSP signalling and establishment.
I have few question about it:

How the ingress node knows about all the egress Node? BGP? Any good document
or link?
Now ingress node knows about the egress node then tunnel will be singaled
using the RSVP so there must be interaction between BGP and RSVP right? If
so then what kind of communication is it? Any good link or documents?
If any one has any good document to share that will be great help, I am
looking for control plane communication between Egress nodes and Ingress
node to establish P2MP LSP.
-- 
David W.