Rendezvous Points - Cisco ASR 9000 Series Configuration Manual

Rendezvous Points

Tip Two PIM routers are neighbors if there is a direct connection between them. To display your PIM neighbors,
use the show pim neighbor command in EXEC mode.
Figure 5: Designated Router Election on a Multiaccess Segment
DR election process is required only on multiaccess LANs. The last-hop router directly connected to the
Note
host is the DR.
Rendezvous Points
When PIM is configured in sparse mode, you must choose one or more routers to operate as a rendezvous
point (RP). A rendezvous point is a single common root placed at a chosen point of a shared distribution tree,
as illustrated in
can be either configured statically in each box or learned through a dynamic mechanism.
PIM DRs forward data from directly connected multicast sources to the rendezvous point for distribution
down the shared tree. Data is forwarded to the rendezvous point in one of two ways:
• Encapsulated in register packets and unicast directly to the rendezvous point by the first-hop router
• Multicast forwarded by the RPF forwarding algorithm, described in the
Cisco ASR 9000 Series Aggregation Services Router Multicast Configuration Guide, Release 6.0.x
88
Figure 4: Shared Tree and Source Tree (Shortest Path Tree), on page
operating as the DR
page 90, if the rendezvous point has itself joined the source tree.
Implementing Layer-3 Multicast Routing on Cisco IOS XR Software
Reverse-Path Forwarding, on
85. A rendezvous point