SSM Deployment Host-side implementation Purpose Specification of interesting source address(es) as well as multicast address (aka (S,G) join/leave) Summarizing and reporting (S,G) information Kernel implementation IGMPv3 for IPv4 and MLDv2 for IPv6 MSF APIs Application implementation MSF APIs Router-side implementation Purpose Translation of reported (S,G) information Constructing SPT from initial phase Routing protocol implementation IGMPv3 for IPv4 and MLDv2 for IPv6 (Currently, PIM-SSM is only the routing protocol to support SSM architecture)