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BSR Hashing Algorithm

Have a network that has 2 C-RPs and an elected BSR.

When a PIMv2 BSR router somewhere in the network receives the group-to-RP mappings from it's PIM neighbor, The group-to-RP mapping (RP-set) has two entries to the for the multicast group. One to RP1 and one to RP2.

The router then runs the BSR hashing algorithm and it selects one of the RPs to be active for that multicast group on that router.

What is the selection mechanism, does the hash algorithm just pick the C-RP with the lowest/highest IP address as the active RP for the group?

HELP !! :-)

  • Other Network Infrastructure Subjects
Cisco Employee

Re: BSR Hashing Algorithm

From the RPs with the highest priority (i.e. lowest `Priority' value), the candidate with the highest resulting value is then chosen as the RP for that group, and its identity and hash value are stored with the entry created.

Ties between RPs having the same hash value and priority, are broken in advantage of the highest address.

You can find this information at:

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