Patent ID: 7894450
Filing Date: 2011-02-22
Classification: H04L

Abstract:
1. A method of implementing a layer 3 Virtual Private Network (VPN) over an underlying Ethernet network, the Ethernet network implementing a link state protocol in a network control plane to enable each Ethernet node to have a synchronized view of a topology of the Ethernet network and to individually populate a forwarding information base according to a computed view of the network, the method comprising the steps of: assigning a VPN I-SID to the VPN, the VPN I-SID being a community of interest identifier with relevance to the network control plane for selective installation of forwarding state in the Ethernet node forwarding information bases, but not used to forward traffic on the Ethernet network; establishing a first Virtual Routing and Forwarding table (VRF) for the VPN on a first node in the link state protocol controlled Ethernet network, assigning the VPN I-SID to the first VRF; advertising the VPN I-SID in a first link state protocol link state advertisement by the first node; establishing a second VRF for the VPN on a second node in the link state protocol controlled Ethernet network; assigning the VPN I-SID to the second VRF; advertising the second attachment of the I-SID in a link state protocol link state advertisement by the second node; and using the VPN I-SID when transmitting packets of data on the link state protocol controlled Ethernet network to allow a node that receives the packets to identify the correct VRF to be used for further handling of the packets.