Patent ID: 8576848
Filing Date: 2013-11-05
Classification: H04L

Abstract:
1. A method in a hierarchical open shortest path first network including an open shortest path first area zero and a non-zero open shortest path first area, the method comprising: determining, at an area border router, an open shortest path first metric representing a cost associated with transporting, within the non-zero open shortest path first area, data between a provider edge router and the area border router; blocking, at the area border router, a packet used to determine the open shortest path first metric from being distributed in the open shortest path first area zero; replacing, at the area border router, a first multiprotocol label switching label included in a border gateway protocol message received from the provider edge router with a second multiprotocol label switching label associated with the provider edge router; replacing, at the area border router, a next-hop attribute included in the border gateway protocol message with a value representing a loopback address of the area border router; updating, at the area border router, a route cost attribute included in the border gateway protocol message to include the open shortest path first metric; and advertising, from the area border router, the border gateway protocol message into the open shortest path first area zero.