Patent ID: 7940685
Filing Date: 2011-05-10
Classification: H04L

Abstract:
1. A method of monitoring a network comprising: establishing at least one tunnel between a monitor in a backbone network and each of at least one of a plurality of provider edge routers, wherein the at least one tunnel is established by the monitor; sending an internet group management protocol join message for a multicast group to the at least one of the plurality of provider edge routers via at least one tunnel of the at least one tunnel, wherein the multicast group is used by a multicast distribution tree of a multicast virtual private network, wherein the join message is sent by the monitor; transmitting a probe packet via a predetermined tunnel of the at least one tunnel to an ingress provider edge router by utilizing the monitor, wherein the probe packet comprises a source address of the monitor and a destination address comprising a multicast group address of the multicast distribution tree, wherein the probe packet comprises identification information for enabling the monitor to identify the probe packet; receiving at least one of the transmitted probe packet and a copy of the probe packet at the monitor from a provider edge router of the plurality of edge routers, wherein each of the transmitted probe packet and the copy of the probe packet comprises information for enabling the monitor to identify the provider edge router that transmitted at least one of the transmitted probe packet and the copy; and joining the monitor to the multicast group, wherein all multicast packets addressed to the multicast group and received at a particular provider edge router are sent to the monitor by an action selected from the group consisting of forwarding and copying, wherein the monitor is configured to identify at least one of the plurality of provider edge routers using information provided by generic routing encapsulation.