SURVIVABILITY ANALYSIS OF COMPLEX COMPUTER-NETWORKS WITH HETEROGENEOUS LINK-CAPACITIES

The paper presents a technique to obtain a survivability index called capacity related reliability (CRR) in large communication-networks where links have different capacities. The network operates successfully as long as a minimum message capacity W(min) can be transmitted through it. We call this scenario a suitable operational environment (OE) to transmit the message. To help obtain an OE, a k-composite path is defined as the union of the set of edges in any k simple paths. The proposed method is a 2-step approach. First, we enumerate k-composite paths that relate link capacity and network connectivity. It is similar to enumerating k-cliques in a path graph. Second, using the composite path information, we generate the CRR that measures the probability of the existence of at least one OE. We have programmed our algorithms using C on Encore Multimax system. The software tool is called SACHEL (Survivability Analysis of complex Computer-networks with Heterogeneous Link-capacities). The experimental results on CRR for a given network with various values of W(min) are presented in tables. The method is efficient and straightforward, and is illustrated with examples.