Improving the Accuracy of Reliability Models for Direct Interconnection Networks.

Fault-tolerance in multicomputer interconnection networks has been traditionally studied by determining the worst possible combination of faulty components that causes a network failure and then assuming that this will occur. But, the worst possible combination may occur with low probability and the routing algorithm may allow the network to work, even when there is a large number of faults. Thus, the network dependability parameters computed according to this approach will be underestimated. In a previous paper [3], we have proposed a new methodology, based on Markov chains, for evaluating interconnection network dependability. Using this methodology, we can accurately compute the network reliability behavior. In this paper we apply it to evaluate dependability parameters in a 2-D mesh, taking into account network size, routing algorithm, failure and repair rates of nodes and coverage. Finally, we compare the computed results under traditional and our approach.