Patent ID: 7606187
Filing Date: 2009-10-20
Classification: H04L,H04W

Abstract:
1. A method for supporting multicast routing in a multi-hop wireless ad hoc network that includes a plurality of fixed infrastructure nodes communicatively coupled to a backbone, the method comprising: selecting certain infrastructure nodes as local multicast group leaders; forming a plurality of local multicast trees each rooted at a local multicast group leader, and each comprising a plurality of members; transmitting a message packet destined for a plurality of destination nodes, wherein each of the plurality of destination nodes is a member of at least one local multicast tree, and further wherein each of the plurality of destination nodes is a member of at least one multicast group identified by a multicast group address associated with the multicast group, from a node to a first local multicast group leader, wherein the message packet includes the multicast group address; forwarding the message packet to the backbone by the first local multicast group leader; receiving the message packet by at least one other local multicast group leader via the backbone; and distributing the message packet to the plurality of destination nodes by each of the at least one other local multicast group leaders distributing the message packet to each member having the multicast group address of its associated local multicast tree, wherein each packet transmitted in multicast or broadcast traffic carries a sequence number in the packet's packet header, the method further comprising: deleting a packet newly received by a node when the packet carries a sequence number that has been previously received by the node; and accepting a packet newly received by the node when the packet carries a sequence number that has not been previously received by the node.