Patent ID: 7035937

Claim:
A method of operating a multicasting communications network comprising the steps of: a) providing a multicasting communications network formed of a plurality of nodes and links connecting said nodes to facilitate communication among said nodes; b) calculating a first multicast routing scheme, said multicast routing scheme defining, for each of said nodes, a plurality of paths for facilitating communication with each of said other nodes in said network, said paths each being formed by one or more of said links; c) calculating one or more alternate multicast routing schemes to be employed if said first multicast routing scheme fails due to failure of one or more of said links or nodes; b) implementing multicasting communications between said nodes in said network by interconnecting said nodes in accordance with said first multicast routing scheme; and d) interconnecting said nodes in accordance with one of said alternate multicast routing schemes if said first multicast routing scheme fails; e) estimating a time at which a probability of said one or more alternate multicast routing schemes failing exceeds a predetermined threshold; f) employing said estimated time to determine a time at which calculation of one or more additional alternate multicast routing schemes should begin; and, g) calculating one or more additional alternate multicast routing schemes at said determined time.