PIM SM Traffic Snooping Overview

When multiple PIM sparse mode (PIM SM) routers connect through a snooping-enabled device, the Ruckus device always forwards multicast traffic to these routers. For example, PIM sparse routers R1, R2, and R3 connect through a device. Assume R2 needs traffic, and R1 sends it to the device, which forwards it to both R2 and R3, even though R3 does not need it. A PIM SM snooping-enabled device listens to join and prune messages exchanged by PIM sparse routers, and stops traffic to the router that sends prune messages. This allows the device to forward the data stream to R2 only.

PIM SM traffic snooping requires IGMP snooping to be enabled on the device. IGMP snooping configures the device to listen for IGMP messages. PIM SM traffic snooping provides a finer level of multicast traffic control by configuring the device to listen specifically for PIM SM join and prune messages sent from one PIM SM router to another through the device.