Performance Metrics in Networks

This chapter introduces the main performance metrics in network design used throughout the book. Link, end‐to‐end, and average network delay estimations are provided for packet switching networks. Several models are presented for evaluating blocking probability in circuit switching networks, including multiclass scenarios where connections of different bandwidths share the links. Average number of hops and network congestion metrics are defined. Cost models are introduced that capture the economies of scale discounts appearing in network equipment acquisitions. Network availability is used for evaluating network resilience, under risks modeled using the Shared Risk Group (SRG) concept. We present a method to estimate network availability in general protection or restoration schemes. Finally, we provide a rigorous definition of fairness in resource allocation and its connection with utility functions. We pursue, when possible, simplified estimations of these metrics that can be introduced in network design models. In such case, their convexity properties are analyzed.