Patent ID: 7856019

Claim:
A method comprising: receiving from a source node a multicast data packet at a transit node, the multicast data packet having a source address and a multicast group address; comparing the source address and the multicast group address of the multicast data packet with a hardware entry of a hardware cache; detecting at the transit node a hardware cache miss for the multicast data packet in response to the comparing not resulting in a match of the hardware entry with the source address and the multicast group address of the multicast data packet; flooding via hardware the multicast data packet to ports of the network in response to detecting the hardware cache miss, wherein the flooding comprises forwarding a copy of the multicast data packet to neighboring nodes of the transit node based on virtual local area network (VLAN) membership; sending a copy of the multicast data packet to an out-of-line processing unit; software-processing the copy of the multicast data packet without forwarding the copy onto the network from the out-of-line processing unit, the software-processing to include establishing a hardware cache entry for the multicast data packet via a hardware abstraction layer; and forwarding a future multicast data packet only to neighboring nodes of the transit node that subscribe to multicast traffic in response to matching a source address and a multicast group address of the future multicast data packet with the hardware cache entry for the multicast data packet.