Reliability evaluation of large telecommunication networks Original Research Article

In this paper, we describe an approximation method to evaluate the reliability of large telecommunication networks based on optic fibre and digital cross-connect systems (DCS). The reliability measures are defined as the availability and the expected lost traffic. Their evaluation is decomposed into the rerouting calculation and the probabilistic calculation. The rerouting calculation (restoration from failures) is accomplished by a heuristic method using the K-shortest paths. It is made very rapidly, thanks to a sophisticated data structure. The probabilistic calculation is based on the stratified sampling which results in computational savings of several orders of magnitude and is well suited to very large networks with high reliability components.