[j-nsp] Bringing DM multicast into a SM domain

[Leonard Giuliano]

On Tue, 18 Apr 2006, Jee Kay wrote:

-) On 13/04/06, Leonard Giuliano <lenny at juniper.net> wrote:
-) 
-) > as the source to the border interface.  This may break unicast
-) > connectivity to that source subnet, though.
-) 
-) Unfortunately we need unicast connectivity to the sources aswell as multicast.
-) 
-) > A simpler alternative that seems to work is to simply make the SM border
-) > router an RP.
-) 
-) Could you expand on this a little? I can't quite see how ir would work.
-) 

The key is having the RP get "tickled" with state so that it knows about a 
source when it receives a (*,G) join.  When mcast data packets hit an RP 
on an interface with PIM-SM configured, this is enough to create the 
necessary state.  This seems to work whether the source is local or 
non-local.