Re: draft-ietf-pim-sm-bsr-02

>I have a concern with respect to draft-ietf-pim-sm-bsr-02.
>
>In the spec it states:
>"Every C-RP periodically unicasts a C-RP-Adv to the BSR for that scope
>zone to inform the BSR of the C-RP's willingness to function as an RP.
>Unless configured otherwise, it does this for every Admin Scope zone for
>which it has state, and for the global scope zone." 
>
>What is the purpose behind allowing a C-RP for a group to advertise itself 
>to the global scope zone BSR once it knows there is a scope zone for the 
>group?    
>
>Routers on the other side of the scope zone boundary will be unable to
>use the C-RP as the RP for the group, yet they will try to do so (depending
>on priorities etc). In other words, group traffic is blackholed in
>any other region.
>
>Is this the intention of the design?

Say there are two scopes, global and scope A.  By default, a C-RP
might be a C-RP for both.  It sends a C-RP-advertisement message to
the global scope BSR advertising it's candidacy to be a global scope
RP, and it also sends a C-RP-adv message to the scope A BSR
advertising it's candidacy to be a scope A RP.  The former message
lists the global scope address range, and the latter message lists the
scope A address range.

Given that global scope and scope A address ranges don't overlap,
what's the problem here?

Cheers,
	Mark