Patent ID: 7969995

Claim:
A method of constructing a forwarding database for a data communications network comprising a plurality of network components and supporting at least first and second topologies having one or more common network components wherein the forwarding database includes at least first and second database structures having records including forwarding information for data destined for related network components in the first and second topologies, each database structure having a plurality of elements including a pointer to one of a succeeding element or a record including said forwarding information, the method comprising the steps, performed at a constructing network component of: identifying a particular network component common to the first and second topologies for which a first record exists in the second database structure; including a pointer from a related element, related to the particular common network component, in the first database structure to a corresponding element or record associated with the first record in the second database structure; and in which the data communications network supports multiple topologies and in which the first topology is an additional topology and the second topology is a base topology; further comprising including a pointer from the first database structure to the second database structure for each network component for which a record does not exist in the first database structure.