Patent ID: 7447203
Filing Date: 2008-11-04
Classification: H04L

Abstract:
1. A method for providing a virtual private network, by receiving from a customer originating device of a first local area network, a local area network frame for transmission to a customer destination device in a second local area network over broadband access links that include customer local area network edge devices of at least one customer and an ingress edge device and an egress edge device of a service provider network, the method comprising: assigning to each edge device of the service provider a unicast IPv6 address, from an IPv6 address block of the service provider, that corresponds to a particular local area network of the customer; assigning to each edge device of the service provider a virtual private network specific multicast IPv6 address, from the IPv6 address block of the service provider, using the virtual private network specific multicasting IPv6 address for multicasting packets to all of the edge devices of the service provider serving the virtual private network; determining whether an IPv6 packet includes a destination address of a customer destination device, and whether the destination address is mapped to an egress edge device of the service provider, when mapping of the destination address to an egress edge device does not exist, encapsulating the local area network frame in a multicast IPv6 packet, the multicast IPv6 packet including the IPv6 address of the ingress edge device of the service provider as the source address and the multicast IPv6 address of the virtual private network as the destination multicast address; when mapping of the destination address to an egress edge device does exist, encapsulating the local area network frame in a unicast IPv6 packet, including the unicast IPv6 address of the egress edge device of the service provider; adding a virtual private network identification header to a header of the IPv6 packet, the virtual private network identification header including a destination option, a virtual private network hop count and an identification number identifying the virtual private network of the customer; broadcasting the IPv6 packets having multicast addresses through the service provider network to all of the edge devices serving the virtual private network; transmitting the IPv6 packets having the unicast IPv6 address, through the service provider network to a particular egress device; authenticating the IPv6 packets at the egress device of the service provider using the virtual private network identification; discarding any IPv6 packets that cannot be authenticated; decapsulating and extracting the local area network frame of authenticated IPv6 packets at the egress device of the service provider; forwarding the decapsulated local area network frame to the destination local area network; and transmitting the decapsulated customer local area network frame to the customer destination device.