Near-optimal virtual path routing for survivable ATM networks

Addresses the problem of virtual path routing for survivable ATM networks. An algorithm is developed to find a virtual path configuration and bandwidth assignment which minimizes the expected amount of lost flow upon network restoration from a failure. The concept of two-step restoration is introduced to achieve fast restoration as well as optimal reconfiguration. The problem can be formulated as a nonlinear nonsmooth multicommodity flow problem with linear constraints. A modified flow deviation approach is developed to obtain the steepest decent direction for a nonsmooth objective function. Based on the proposed scheme, convergence to a near-optimum is possible by properly adjusting optimization parameters