tailieunhanh - Observing the Evolution of Internet AS Topology 

Characterizing the evolution of Internet topology is important to our understanding of the Internet architecture and its interplay with technical, economic and social forces. A major challenge in obtaining empirical data on topology evolution is to identify real topology changes from the observed topology changes, since the latter can be due to either topology changes or transient routing dynamics. In this paper, we formulate the topology liveness problem and propose a solution based on the analysis of BGP data. We find that the impact of transient routing dynamics on topology observation decreases exponentially over time, and that the real topology dynamics consist of a constant-rate birth process and a constant-rate. | Observing the Evolution of Internet AS Topology Ricardo Oliveira University of California Los Angeles CA rveloso@ Beichuan Zhang University of Arizona Tucson AZ bzhang@ Lixia Zhang University of California Los Angeles CA lixia@ ABSTRACT Characterizing the evolution of Internet topology is important to our understanding of the Internet architecture and its interplay with technical economic and social forces. A major challenge in obtaining empirical data on topology evolution is to identify real topology changes from the observed topology changes since the latter can be due to either topology changes or transient routing dynamics. In this paper we formulate the topology liveness problem and propose a solution based on the analysis of BGP data. We find that the impact of transient routing dynamics on topology observation decreases exponentially over time and that the real topology dynamics consist of a constant-rate birth process and a constant-rate death process. Our model enables us to infer real topology changes from observation data with a given confidence level. We demonstrate the usefulness of the model by applying it to three applications providing more accurate views of the topology evaluating theoretical evolution models and empirically characterizing the trends of topology evolution. We find that customer networks and provider networks have distinct evolution trends which can provide an important input to the design of future Internet routing architecture. Categories and Subject Descriptors Network Architecture and Design Network topology General Terms Measurement Theory Keywords Internet topology topology evolution This work is partially supported by the National Science Foundation under Contract No. CNS-0520318. Opinions and findings expressed in this paper are those of the authors and do not necessarily reflect the views of NSF. Ricardo Oliveira was supported by a scholarship from FCT Portugal ref. SFRH BD 17268 .

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