因特网AS 级拓扑的健壮性测度与健壮性演化

Abstract

The inter-domain routing system consisting of autonomous systems (AS) is the key infrastructure of the Internet. It is critical to study the robustness of the Internet AS topology for the design of the robustness of the whole Internet. The Northeast Blackout (2003) and the Taiwan earthquakes (December of 2006 and March of 2010) reveal that the robustness of todays Internet still needs to be improved. Taking into account both basic theory of network topology and practical compliance to routing policies, this paper investigates the robustness measurement and evolution of the Internet AS topology at two scales: 1)we propose a method for measuring the robustness of individual ASes against AS link and node failures; 2)we propose a k-fault tolerant model for measuring the robustness of the global AS topology; 3)based on the two measuring methods, we present mechanisms and methods for the robustness evolution at both of the scales. Studying on todays real AS topology, we find that: 1)25.8% of all ASes bear even single AS link failures, and 26.4% of all ASes cannot are still vulnerable to single AS node failures; 2)augmenting existing AS topology to <italic>k</italic>-fault tolerance cannot only guarantee the reachability of any node pairs under arbitrary <italic>k</italic> failures, but also providing significantly better robustness under cases of more than <italic>k</italic> failures.