Patent ID: 7096281

Claim:
A method of improving connectivity among topology subnets using a common connection network, comprising: determining, by a border node located at a border of a particular one of the topology subnets, one or more links between the border node and a neighboring border node located at the border of a different one of the topology subnets, wherein a first session endpoint resides in the particular one of the topology subnets and has connectivity to a global virtual routing node (“GVRN”); creating a list of the determined links; determining that the first session endpoint has connectivity to the GVRN and adding link information to the created list to represent the determined connectivity of the first session endpoint to the GVRN; forwarding the list to the neighboring border node; receiving, at the neighboring border node, the list; determining whether a second session endpoint, which resides in the different one of the topology subnets, has connectivity to the GVRN or to another GVRN, and, when the second session endpoint has connectivity to the GVRN or to another GVRN, adding link information to the list to represent the determined connectivity; and using the list to select a data transmission path between the first session endpoint and the second session endpoint.