Configure SSM to optimize PIM-SM by simplifying the many-to-many model (servers-to-receivers).
Configure a unicast protocol, for example, Routing Information Protocol (RIP) or Open Shortest Path First (OSPF), globally and on the interfaces where you want to configure PIM. For more information about RIP, see RIP configuration using CLI. For more information about OSPF, see OSPF configuration using CLI.
Enable PIM globally.
Because most multicast applications distribute content to a group in one direction, SSM uses a one-to-many model that uses only a subset of the PIM-SM features. This model is more efficient and reduces the load on multicast routing devices.
SSM is a global configuration. After you enable SSM on a switch, it is enabled on all interfaces that run PIM. On an SSM-enabled switch, SSM behavior is limited to the SSM group range.
For non-SSM groups, the protocol behavior is PIM-SM.
enable
configure terminal
ip pim mode ssm