Reliability Evaluation Of Communication Network Research Articles

161 Reliability evaluation of communication networks

161 Reliability evaluation of communication networks

Reliability Evaluation of Communication Networks

In the evaluation of the capacity of a communication network architecture to resist to the possible faults of some of its components, several reliability metrics are currently used. The evaluation of these metrics is in general a very costly task since most of them are, as algorithmic problems, classed in the NP-hard family. As a consequence, many different techniques have been proposed to solve them. We discuss here a promising class of methods called “factorization” and some of the implementation issues. An alternative approach to these exact techniques is to perform statistical estimations using a Monte Carlo simulation. It allows to deal with larger networks (having, say, hundreds of components) if the user accepts probabilistic answers. In the case of highly reliable networks, the standard Monte Carlo technique is also prohibitively expensive and variance reduction techniques must be used. We propose here a new Monte Carlo algorithm specifically designed to this context. For both approaches, exact and simulation algorithms, numerical results are provided allowing a comparison and giving an idea of the performances that can be expected.

Enumeration of k-trees and their application to the reliability evaluation of communication networks

In this paper a method is proposed for the enumeration of all the k-trees in a network, and a new algorithm is introduced which uses the k-trees for evaluating the k% reliability, i.e. the probability that at least k% of the network nodes are connected. This reliability measure is more general and gives the well known overall reliability as a special case. The proposed method evaluates this measure using the concepts of Petri nets.