Patent ID: 7574526

Claim:
A method for managing multicast groups in an InfiniB and system area network, the method comprising: end nodes in the InfiniBand and system area network being final destinations for packets; end nodes not including switches or routers, wherein packets are not routed through the end nodes; receiving, by a Subnet Administration in a first InfiniBand end node, a join request from a second InfiniBand end node for joining a multicast group, wherein the second end node is connected to a first switch and wherein the join request is a send-without-receive request that specifies that the second InfiniBand end node is to be a send-without-receive member of the multicast group that can send packets but will not receive packets, and wherein the first InfiniBand end node is included within the InfiniBand system area network, and further wherein switches in the InfiniBand system area network will route packets from the second InfiniB and end node but will not route any packets to the second InfiniB and end node; determining whether the multicast group exists; and if the multicast group does not exist, creating, by the Subnet Administration in the first InfiniBand end node, the multicast group and routing the first switch to discard all packets for the multicast group, wherein when the multicast group is created, the second InfiniBand end node is the only member of the multicast group and the multicast group includes no members that will receive packets.