Patent ID: 7948927

Claim:
A packet relay method for relaying an explicit multicast packet from a home agent that manages home and care of addresses of one or more mobile nodes where the one or more mobile nodes are movable among networks, the method comprising: receiving, at the home agent, an explicit multicast packet that includes a plurality of receivers' addresses written in a list of receivers' addresses, the explicit multicast packet having a home address of one of the one or more mobile nodes managed by the home agent designated as a destination address of the packet; analyzing, at the home agent, whether or not packet-undelivered addresses written in the list of receivers' addresses in the packet are home addresses of the one or more mobile nodes managed by the home agent; and relaying the packet based on a result of the analysis, wherein relaying the packet based on the result of the analysis further comprises rewriting the home addresses of the one or more mobile nodes in the list of receivers' addresses as corresponding care of addresses of the one or more mobile nodes.