Small-World Phenomena in Communications Networks : A Cross-Atlantic Comparison

This paper examines small-world phenomena in communications systems focusing specifically on three networks each operating in different geographical spheres. The first is the logical IP (Internet Protocol) fibre optic infrastructure that connects major metropolitan areas in the United States (for the years 1997 through 2000), the second a portion of the Italian phone network using outgoing landline calls by district to capture network traffic dynamics, while the third one is a Peer-to-Peer (P2P) data network for the international exchange of music for a particular group of independent people. Power-law distributions are generated for each network to look for scale-free properties. The implications of the results of these experiments for transportation policy and planning, and the way in which they may vary depending on geography – i.e., for example, whether or not a network operates in Europe versus the United States, or whether it is one with no geographical boundaries and rather an international dimension – are hypothesized although a more thorough investigation of this is warranted. Also the paper offers some thoughts about the analytical methodologies, visualization techniques and data that are needed to facilitate a valid and informative cross-Atlantic comparison of communications networks in this context