Source-linked AI summary
Inter-similarity between coupled networks
Roni Parshani, Celine Rozenblat, Daniele Ietri, Cesar Ducruet, Shlomo Havlin
TL;DR
Random interdependencies make coupled networks highly vulnerable, whereas real networks may exhibit structured inter-similarity. The paper measures inter-similarity with IDDC and ICC, develops a generation mechanism, and finds that greater inter-similarity substantially improves robustness to random failure.
Problem
Existing analyses commonly assume random interdependencies, although real coupled infrastructures often pair structurally similar nodes; limited theoretical tools constrain analysis of these systems.
Method
The paper quantifies inter-similarity using inter degree-degree correlation (IDDC) and inter-clustering coefficient (ICC), develops a generalized BA model, and analyzes simulations plus port-airport networks.
Results
Greater inter-similarity makes interdependent networks significantly more robust to random failure, reduces cascading-failure iterations, and changes disintegration from a first-order to a second-order phase transition.
Takeaways & Limitations
Well-connected ports tend to couple with well-connected airports, supporting structured rather than random interdependencies in real coupled networks.
Takeaways & Limitations
The port-airport analysis assumes a node becomes nonfunctional when 75 percent of its traffic is disabled.
Abstract
from arXiv · showhide
Recent studies have shown that a system composed from several randomly interdependent networks is extremely vulnerable to random failure. However, real interdependent networks are usually not randomly interdependent, rather a pair of dependent nodes are coupled according to some regularity which we coin inter-similarity. For example, we study a system composed from an interdependent world wide port network and a world wide airport network and show that well connected ports tend to couple with well connected airports. We introduce two quantities for measuring the level of inter-similarity between networks (i) Inter degree-degree correlation (IDDC) (ii) Inter-clustering coefficient (ICC). We then show both by simulation models and by analyzing the port-airport system that as the networks become more inter-similar the system becomes significantly more robust to random failure.