Dynamic Coupling Strategy for Interdependent Network Systems Against Cascading Failures

TL;DR

This paper introduces a dynamic coupling strategy that adjusts inter-network flow redistribution coefficients in real-time to significantly improve robustness against cascading failures in interdependent network systems.

Contribution

It proposes a novel Step-wise Optimization (SWO) method that dynamically tunes coupling coefficients, enhancing robustness and scalability over fixed-coupling approaches.

Findings

SWO significantly reduces cascading failures in simulations.

The method outperforms fixed coupling strategies in robustness.

SWO is computationally efficient and adaptable to various network topologies.

Abstract

Cascading failures are a common phenomenon in complex networked systems where failures at only a few nodes may trigger a process of sequential failure. We applied a flow redistribution model to investigate the robustness against cascading failures in modern systems carrying flows/loads (i.e. power grid, transportation system, etc.) that contain multiple interdependent networks. In such a system, the coupling coefficients between networks, which determine how much flows/loads are redistributed between networks, are a key factor determining the robustness to cascading failures. We derive recursive expressions to characterize the evolution of such a system under dynamic network coupling. Using these expressions, we enhance the robustness of interdependent network systems by dynamically adjusting the coupling coefficients based on current system situations, minimizing the subsequent failures. The analytical and simulation results show a significant improvement in robustness compared to prior work, which considers only fixed coupling coefficients. Our proposed Step-wise Optimization (SWO) method not only shows good performance against cascading failures, but also offers better computational complexity, scalability to multiple networks, and flexibility to different attack types. We show in simulation that SWO provides robustness against cascading failures for multiple different network topologies.