Protocol Independent Multicast (PIM) enables efficient data distribution by connecting one-to-many and many-to-many nodes. This document focuses on PIM Sparse Mode (PIM-SM), the only supported PIM model.
PIM-SM ensures fast and efficient data delivery to participating nodes, requiring at least three configured routers. It is ideal for customers needing automatic updates for specific network devices. For example, retail customers can push video streams to multiple store monitors, showcasing products without manually updating each receiver. Any receiver that contacts the Rendezvous Point (RP) is automatically updated.
Each PIM-SM-enabled device must configure a static RP router to a group mapping, and all PIM-SM-enabled devices must have the same RP to group mapping configuration. PIM relies on unicast routing to be configured and operational for Reverse Path Forwarding (RPF) operations, so you must additionally configure a routing protocol or static routes.
Consider this basic PIM-enabled network example, which includes three routers, a source, and a receiver: