Patent ID: 8625603

Claim:
A method comprising: detecting a reverse path forwarding (RPF) check failure, wherein the detecting is performed in response to receipt of a multicast packet via an incoming port, and wherein the RPF check failure indicates that the incoming port is not a RPF port on a reverse path back to a multicast source that sent the multicast packet; determining that the incoming port via which the multicast packet was received is part of a virtual local area network (VLAN), in response to the RPF check failure; querying a table for information about the VLAN, wherein the table comprises data derived from neighborhood discovery protocol (NDP) messages, in response to the determining; and causing an NDP message to be sent to at least one network node, wherein the NDP message causes new VLAN information to be provided for inclusion in the table, in response to a result of the querying indicating that the new VLAN information is needed.