Performability analysis of large-scale packet switching networks

An efficient computable measure of performability, the combination of performance and reliability, in packet switching networks is presented. The impact of the network´s reliability on response time is examined. Packet delivery, the probability Pr(τ⩽t ) that the delay τ for a packet transmission does not exceed a specified time t, is used as a measure of response time. Delay of a packet results if the system is busy servicing other packets or if equipment in the network is malfunctioning. The method for estimating performability for complex packet switching networks is based on constructing a bounding structure whose packet delivery is a lower bound on the packet delivery in the underlying network. The proposed method can be used also for evaluation and improvement of the response time for the problem of transaction processing for different network configurations