Rp Selection - HP ProCurve Secure Router 7203 dl Advanced Management And Configuration Manual

RP Selection

When a router adds an entry for a new group to its multicast routing table, it
must determine the RP for that group. The router searches its RP set for up
to four routers that can support that group. An RP set includes the IP address
of every router allowed to become an RP and the multicast groups that each
router can support.
The router then hashes each potential RP's address with the multicast group's
address. The RP that produces the highest hash value becomes the RP for the
group. Because all routers use the same hash function, they will always agree
on the same RP for a group as long as they are using the same RP set.
PIM-SM allows these methods for distributing an RP set:
Automatic—An administrator configures routers to be RP candidates
(RP-Cs). A bootstrap router (BSR) collects advertisements from the RP-
Cs and, from them, compiles an RP set. The BSR distributes the RP set to
each PIM router in the domain.
Static—The administrator manually configures the same RP set on each
PIM router in the domain.
The ProCurve Secure Router supports static RP selection only. You can
configure RP sets that contain:
a single RP, which supports all multicast groups
multiple RPs, each of which can potentially support any group
multiple RPs, each of which supports only a specific set of groups
multiple RPs, some of which can support any group and some of which
are limited to certain groups
You must configure the same router to be RP for same set of addresses on
each router in the PIM domain. For example, if you want to configure Router
A to be the RP for multicast groups 224.0.0.0 through 231.255.255.255 in the
network shown in Figure 11-7, then you must specify this configuration on
Routers A, B, and C. Similarly if you want Router B to support all groups, you
must specify this on each router, not only on Router B.
Configuring Multicast Support with PIM-SM
Overview
11-17