Patent ID: 8675653

Claim:
A method of implementing Internet Protocol (IP) Multicasting in a communication network, the method comprising: defining a multicast Static-Range, being a set of Class D IP addresses that do not use a Protocol Independent Multicast (PIM) protocol and do not overlap with an existing Source Specific Multicast (SSM) IP address range; reserving each IP address within the multicast Static-Range for static IP multicasting; establishing, in the communication network, at least one dynamic IP multicasting group, the at least one dynamic multicasting group having a respective IP address lying outside the multicast Static-Range; establishing, in the communication network, at least one static multicasting group for which both PIM-Source Specific Mode (PIM-SSM) messaging and PIM-Sparse Mode (PIM-SM) messaging are ignored, the at least one static multicasting group having a respective IP address lying within the multicast Static-Range; establishing static multicast connections for all upstream routers from a host router toward a source, wherein dynamic multicast states and static multicast states are both added and removed independently; after all upstream connections are established, upon receipt of an IGMP message from a host at the host router, determining whether the multicast group address therein is within the multicast Static-Range; if the multicast group address is within the multicast Static-Range and the IGMP message is an IGMP JOIN message, building a connection between a downstream outgoing interface (OIF) leading to the host and an upstream ingoing interface (IIF) leading to the source without forwarding a PIM message; and if the multicast group address is within the multicast Static-Range and the IGMP message is an IGMP LEAVE message, tearing down the connection between the OIF and IIF without forwarding a PIM message.