Analysis On The Evolving Principle Of The Internet At The AS Level Based On Complex Network

Complex networks describe a wide range of systems in nature and society. Frequently cited examples include Internet, WWW, a network of chemicals linked by chemical reactions, social relationship networks, citation networks, etc. In recent years, the research on complex network has been developing rapidly and is extended to many science fields, such as biology, physics and even social science. It boils down to the first reason is with the improvement of computing capability, people can do research in various realistic networks including multimillion nodes which could not be realized in the past, the second reason is they also need to recognize various networks urgently to find out instructional rules. Complex systems are all described through the complex networks. The aim of the studies on these networks is to investigate their mechanisms, understand their developing rules and find the relationship between their structure and the complex functioning processes on them, so as to accumulate the knowledge about the natural disciplinarians dominating the complex systems.This thesis aims mainly at the research on evolving principle of the Internet at the AS level. In this thesis, the research background and new development for complex network are introduced briefly. Meanwhile we also show the network about the Internet at the AS level, then we investigate several important topological parameters of complex networks, whose principle and evolving reason are mainly analyzed in detail. The main contents are outlined as follows:(1) HUB evolving principle of the Internet at the AS level and its effect on the network topology is studied. In complex networks, the majority of nodes are connected to few links, while some nodes (called HUB) are attached to a large number of links. In this thesis, evolving data of the Internet at the AS level are analyzed by calculating the proportion of the degrees of 20%,10%,5% largest nodes , degree larger than 300, degree between 100 and 300 to the total degrees in the networks for the research on the evolving principle of degrees and numbers of HUB.(2) Scale free property evolving of the Internet at the AS level is analyzed. In the thesis, we discuss how the Internet at the AS level changes in time by calculating degree variance, degree-rank exponent and Gini coefficient .Furthermore, we analyze the reason of evolving in the network..(3) Network structure entropy of the Internet at the AS level is discussed. It can be used as a better method for research on inhomogeneity of complex networks. In the thesis, we also analyzed the evolving and its reason of the Internet at the AS level.