Identifying Sensitive Components in Infrastructure Networks via Critical Flows

Abstract

This paper introduces a novel set of component importance measures that are based on the concept of critical flow. Various research communities have developed techniques for identifying critical components of networks. The methods in this paper extend previous work on flow-based centrality measures by incorporating insights from both critical infrastructure protection and urban planning. The motivation is to provide municipalities with a means of reasoning about the impact of urban interventions. An infrastructure system is represented as a flow network in which demand nodes are assigned both demand values and criticality ratings. Sensitive elements in the network are those that carry critical flows, where a flow is deemed critical to the extent that it satisfies critical demand. A method for computing these flows is presented, and its utility is demonstrated by comparing the new measures to existing flow centrality measures. The paper also shows how the method may be combined with a simple form of reliability analysis.

Critical flow centrality measures on interdependent networks with time-varying demands

“…Computation of the centrality measure, critical flow centrality ("CFC"), can be accomplished in several ways (see [57]). In the current paper, a discrete-valued approach is taken in which: (1) an infrastructure system is represented as a flownetwork;…”

“…One can model a water system using hydraulic techniques [58], for example, coupling it to an electricity system that is simulated using its own domain-specific methods. Given a flow solution and network topology, CFC values can be computed by using Markov-chain Monte Carlo or random walks (see [57] for details).…”

“…The Critical Flow Centrality ("CFC") of a component is a measure of its role in supplying resources to critical locations [57]. Recall that the flow in network (given assignment ) is the aggregate of all flows reaching the demand nodes:…”