Patent ID: 7180864

Claim:
A method for communicating routes in a packet-based network, the method for use at a first router comprised in a first autonomous system, the method comprising the steps of: receiving a first routing message in conformance with a Border Gateway Protocol from a peer router of said first router, the first routing message comprising a first path from the first autonomous system to a destination, the first path from the first autonomous system to the destination including a second autonomous system, the second autonomous system being a next hop of said first path; receiving a second routing message in conformance with a Border Gateway Protocol from a peer router of said first router, the second routing message comprising a second path from the first autonomous system to the destination, the second path from the first autonomous system to the destination being different from the first path from the first autonomous system to the destination, the second autonomous system also being a next hop of said second path; and sending a third routing message to one or more internal peer routers of said first router, said one or more internal peer routers comprised in said first autonomous system, the third routing message comprising at least both the first path from the first autonomous system to the destination and the second path from the first autonomous system to the destination, wherein the first path and the second path have been selected from a set of paths from the first autonomous system to the destination, each of said paths having said second autonomous system as a next hop thereof, and wherein said first path and said second path have equal and maximum values of a degree-of-preference attribute among the paths in said set of paths from which the first path and the second path have been selected, equal and minimum values of a length of an autonomous-system-path attribute among the paths in said set of paths from which the first path and the second path have been selected, and equal and minimum values of a multi-exit-discriminator attribute among the paths in said set of paths from which the first path and the second path have been selected.