Re-routing in circuit switched networks

Dynamic routing has been adopted in many circuit switched networks in many parts of the world. A number of dynamic routing schemes have been designed and studied with the aim of maximizing the network throughput. The least loaded routing (LLR) is simple and efficient, while other more elaborate routing schemes can only provide marginal throughput gain over that of LLR. Re-routing is the practice of routing calls on alternate paths to direct paths or other less congested alternate paths. It allows the continuous redistribution of network loads so that the congestion on direct paths can be relieved. We study a re-routing scheme based on LLR. An original analysis of re-routing is performed and numerical examples confirm the significant throughput gain over LLR routing.