31-3
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 31 Configuring PIM Snooping
Understanding How PIM Snooping Works
Figure 31-2 PIM Join Message Flow with PIM Snooping
Figure 31-3
shows the flow of data traffic without PIM snooping enabled. In the figure, the switches
flood the data traffic intended for Router A to all connected routers.
Figure 31-3 Data Traffic Flow without PIM Snooping
Figure 31-4
shows the flow of data traffic with PIM snooping enabled. In the figure, the switches forward
the data traffic only to the router that needs to receive it (Router A).
Router C
Router D
Router B
Router A
(*, G) PIM join
RP Source
Receiver
IGMP join
99474
SP network
Router C
Router D
Router B
Router A
RP Source
Receiver
Data
99472
SP network
G traffic