System Travel Time Reliability: A Measure of the Quality of Service of Networks

In this study, the travel time reliability of network systems is measured by travel time limitation as well as two‐terminal reliability. In the network, each arc is a binary random variable weighted by travel time as well as by operational probability. The performance index or QoS of a network system indicates the probability that the source node can successfully travel to the destination node, while satisfying the travel time limitation. Unlike existing literature that evaluated travel time reliability via a single optimization path, the proposed index focuses on the performance of the entire network system. This study presents an efficient decomposition method in computing QoS based on the Dijkstra shortest path method. We employ a small network to demonstrate the algorithm step by step. In addition, computational experiments conducted on a prototype network show that the proposed algorithm is superior to existing methods.