Brocade FastIron Ethernet Switch IP Multicast Configuration Guide - Manual (Page 166)

IPv6 PIM Sparse
IPv6 Protocol Independent Multicast (PIM) Sparse is supported. IPv6 PIM Sparse provides
multicasting that is especially suitable for widely distributed multicast environments.
In an IPv6 PIM Sparse network, an IPv6 PIM Sparse router that is connected to a host that wants to
receive information for a multicast group must explicitly send a join request on behalf of the receiver
(host).
FIGURE 10 Example IPv6 PIM Sparse domain
PIM Sparse router types
Routers that are configured with PIM Sparse interfaces also can be configured to fill one or more of
the following roles:
• BSR - The Bootstrap Router (BSR) distributes RP information to the other PIM Sparse routers
within the domain. Each PIM Sparse domain has one active BSR. For redundancy, you can
configure ports on multiple routers as candidate BSRs. The PIM Sparse protocol uses an election
process to select one of the candidate BSRs as the BSR for the domain. The BSR with the
highest BSR priority (a user-configurable parameter) is elected. If the priorities result in a tie, then
the candidate BSR interface with the highest IP address is elected. In the example in
Figure 10 on
page 164, PIM Sparse router B is the BSR. Port 2/2 is configured as a candidate BSR.
• RP - The Rendezvous Points (RP) is the meeting point for PIM Sparse sources and receivers. A
PIM Sparse domain can have multiple RPs, but each PIM Sparse multicast group address can
have only one active RP. PIM Sparse routers learn the addresses of RPs and the groups for
which they are responsible from messages that the BSR sends to each of the PIM Sparse routers.
In the example in
Figure 10 on page 164, PIM Sparse router B is the RP. Port 2/2 is configured as
a candidate Rendezvous Point (RP).
To enhance overall network performance, the device uses the RP to forward only the first packet from
a group source to the group receivers. After the first packet, the device calculates the shortest path
IPv6 PIM Sparse
164 FastIron Ethernet Switch IP Multicast Configuration Guide
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