When IGMP snooping is enabled in a VPLS service, IGMP messages received on SAPs and SDPs are snooped to determine the scope of the flooding for a specified stream or (S,G). IGMP snooping operates in a proxy mode, where the system summarizes upstream IGMP reports and responds to downstream queries. For a description of IGMP snooping, see the 7450 ESS, 7750 SR, and VSR Triple Play Service Delivery Architecture Guide, "IGMP Snooping".
Streams are sent to all SAPs and SDPs on which there is a multicast router (either discovered dynamically from received query messages or configured statically using the mrouter-port command) and on which an active join for that stream has been received. The Mrouter port configuration adds a (*,*) entry into the MFIB, which causes all groups (and IGMP messages) to be sent out of the respective object and causes IGMP messages received on that object to be discarded.
Directly-connected multicast sources are supported when IGMP snooping is enabled.
IGMP snooping is enabled at the service level.
IGMP is not supported in the following:
B-VPLS, routed I-VPLS, PBB-VPLS services
a router configured with enable-inter-as-vpn or enable-rr-vpn-forwarding
the following forms of default SAP:
*
*.null
*.*
a VPLS service configured with a connection profile VLAN SAP