Patents Assigned to Nortel Network, Ltd.
  • Patent number: 7894450
    Abstract: Nodes on a link state protocol controlled Ethernet network implement a link state routing protocol such as IS-IS. Nodes assign an IP address or I-SID value per VRF and then advertise the IP addresses or I-SID values in IS-IS LSAs. When a packet is to be forwarded on the VPN, the ingress node identifies the VRF for the packet and performs an IP lookup in customer address space in the VRF to determine the next hop and the IP address or I-SID value of the VRF on the egress node. The ingress node prepends an I-SID or IP header to identify the VRFs and then creates a MAC header to allow the packet to be forwarded to the egress node on the link state protocol controlled Ethernet network. When the packet is received at the egress node, the MAC header is stripped from the packet and the appended I-SID or IP header is used to identify the egress VRF.
    Type: Grant
    Filed: June 26, 2008
    Date of Patent: February 22, 2011
    Assignee: Nortel Network, Ltd.
    Inventors: Paul Unbehagen, David Allan, Bruno Germain, Roger Lapuh, Mohnish Anumala, Nigel Bragg