A simple and new algorithm for capacity related reliability analysis of ATM transport networks

Since high availability requirements are expected to increase in the B-ISDN era, adequate methods are needed which allow network designers and operators to outline the relation between available network resources and actual traffic demands on the one hand, and the reachable availability for either the whole network or individual source-destination VP (virtual path) connections on the other hand. A performance index for a transport network is defined as a composite index integrating the important aspects of reliability, heterogeneous link capacities, non-uniform traffic demands, instantaneous paths-layout, resource-sharing policy, and restoration capability. This paper suggests a simple and thus fast method for deriving the symbolic expression of the performance index in a compact form, from which a "capacity related reliability polynom" may easily be derived. Since the capacity of several subnetworks must be computed taking restoration capability into account, an efficient procedure for capacity determination is also suggested. An example illustrates the procedure and points out the simplicity of the resulting symbolic expressions.