System information

BSR 64000 Configuration and Management Guide
8-4
Delaying Shortest Path Tree Usage for Better Throughput
You can control the data threshold rate to delay when the PIM rendezvous point (RP)
switches to the Shortest Path Tree (SPT) in order to enhance throughput on your
multicast network. The SPT threshold determines when the RP (shared tree) can join
the SPT (source tree) for a specified multicast group. If the RP sends at a rate greater
than or equal to the specified kbps rate, the last-hop router or RP router triggers a PIM
Join message to the PIM source router to construct an SPT.
• If you want to specify the multicast traffic threshold that must be reached on the
RP router before the multicast traffic is switched over to the SPT, use the ip pim
spt-threshold rp command in Global Configuration mode, as shown below:
MOT(config)#ip pim spt-threshold rp <n> [infinity]
where:
n is the multicast traffic rate in kilobytes per second (kbps).
infinity indicates that the RP is always used.
• If you want to specify the multicast traffic threshold that must be reached on the
last-hop router before multicast traffic is switched over to the SP, use the ip pim
spt-threshold lasthop command in Global Configuration mode, as shown below:
MOT(config)#ip pim spt-threshold lasthop <n> [infinity]
where:
n is the multicast traffic rate in kilobytes per second (kbps).
Note: The default setting for the ip pim spt-threshold rp command is 0
kbps, which allows the RP to join the SPT immediately.
Note: The default setting for the ip pim spt-threshold lasthop command is
1024 kbps, which allows the RP to join the SPT when the 1024 Kbps
threshold is reached.