A COMPUTER APPROACH FOR RELIABILITY EVALUATION OF TELECOMMUNICATION NETWORKS WITH HETEROGENEOUS LINK-CAPACITIES

The paper presents a computer approach to obtain a survivability index called capacity related reliability (CRR) in large telecommunication networks where links have different capacities. The proposed method is a 2-step approach. Step 1 deals with composite path enumeration (CPE). A k-composite path is defined as the union of the set of edges in any k simple paths and relates link capacity and network connectivity. The CPE approach, presented in the text, is an improvement over the algorithms of [1]. Step 2 manipulates k-composite paths information to generate the CRR. The paper uses CAREL [4] to solve this step. However, any existing techniques based on Boolean concept, probability theory, inclusion-exclusion principle, etc, [2-7] may also be utilized. The technique is automated using C on Encore Multimax System. The results on CRR for three networks with various values of minimum message capacity are presented in tables. An exhaustive technique is used to verify these results. However, an informal proof of the CPE approach is also included. Appendix A provides the implementation details of the technique. We have given counter examples (refer to Appendix B) for the algorithms of [10, 13] to show that these methods lead to incorrect conclusions under certain situations.