Paper. Journal of World Academy of Science, Engineering and Technology – 2005. – №12 – pp. 426-430.Estimating the reliability of a computer network has been a subject of great interest. It is a well known fact that this problem is NP-hard. In this paper we present a very efficient
combinatorial approach for Monte Carlo reliability estimation of a network with unreliable nodes and unreliable edges. Its core is the computation of some network combinatorial invariants. These
invariants, once computed, directly provide pure and simple framework for computation of network reliability. As a specific case of this approach we obtain tight lower and upper bounds for
distributed network reliability (the so called residual connectedness reliability). We also present some simulation results.
