Approximating dependability measures of FDDI networks

An approximation technique is presented to evaluate the dependability of computer networks. This technique, based on the most likely paths to failure, is simple and practical. It may easily be applied by a network designer in evaluating and comparing different network configurations. The approximation technique is applied to a variety of FDDI network configurations. The effect of certain network parameters on the network availability are examined. From these results the authors conclude that, in order to guarantee high availability, an FDDI network backbone should be interconnected using dual attachment concentrators. Furthermore, dual-homing configurations are required for high availability paths between end-stations and the backbone. For less stringent availability requirements, single attachment concentrator trees with single attachment stations may suffice