Routing and capacity allocation for multirate and multipoint circuit-switched networks

In this paper, some routing and capacity allocation problems for multirate and multipoint circuit-switched networks are formulated and solved. Given are N nodes or points and stationary traffic rates for call arrivals between arbitrary pairs of points and among arbitrary subsets of points. When sufficient capacity is available, traffic will be carried along primary routes belonging to the network. Overflow traffic due to call blocking on primary routes can be carried on alternate routes belonging to a third party carrier. The third party offers circuit-switched capacity on a point-to-point basis at a cost proportional to the carried load. Point-to-point circuit-switched voice traffic is considered first. Integrated point-to-point voice and video traffic are then incorporated into the optimization problem, where it is assumed that the third party carrier can also offer the higher-rate circuit-switched capacity between all pairs of points. Finally, a multipoint routing problem is discussed and a modified flow-deviation algorithm is suggested for its solution. The algorithm incorporates a minimum spanning tree heuristic to compute an approximation to a Steiner tree in each iteration