Source Specific Multicast (SSM) is a datagram delivery model that best supports one-to-many applications, also known as broadcast applications. SSM is networking technology that targets audio and video broadcast application environments.
To configure PIM SSM, you enable PIM SSM on the router and define the SSM range of IP multicast addresses.
To use PIM SSM, IGMPv3 must be configured on customer premise equipment (CPE)–facing interfaces to receivers, and PIM sparse mode must be configured on CPE-facing interfaces to sources and on core-facing interfaces. After configuring SSM, you can use the show ip pim sparse-mode sg-state command to display SSM group membership information.
To configure PIM SSM:
- host1(config)#access-list 15 permit ip any
host 239.0.0.2
- host1(config)#access-list 15 permit ip any 232.0.0.0 0.225.225.225
- host1(config)#ip pim ssm range 15
PIM SSM also works with IGMPv2 if you configure the ssm-map in IGMP as in the following example:
- host1(config)#ip pim ssm
- host1(config)#access-list ssm_map1 permit
232.0.0.1 255.255.255.255
- host1(config)#ip igmp ssm-map enable
- host1(config)#ip igmp ssm-map static ssm_map1
51.0.0.1
The no version disables ssm-map:
- host1(config)#no ip igmp ssm-map static ssm_map1
51.0.0.1
ip pim ssm
- host1(config)#ip pim ssm
- host1(config)#access-list alist permit any
223.0.0.0 0.255.255.255
- host1(config)#ip pim ssm range alist
- host1(config)#ip pim ssm default