An Improved BA Model And Its Application

Recently,the outside pay more attention to the research of complex network, including the use of complex network model, especially BA scale-free network model, simulating the real network is widely applied in the field of physics, biology, and computer field of study etc. Now according to the real network’s some internal features, In order to better simulate the real network more accurately, putting forward a variety of extension models of BA scale-free network to simulate the real network lays a foundation of the further research of inner characteristics and how to control the real network mechanism by the parameters. This article will mainly study it from three aspects:First of all, this paper describes the background and statistical characteristics of some classical models of complex network, introduces several extension models of BA scale-free network and its construction algorithm, refers to this topic research direction.Secondly, this paper analyzes the shortage of traditional BA scale-free model application in the real network. According to the growth and priority connectivity features of real network, an improved BA scale-free model will be came up with, and gives the specific structure algorithm of the improved BA scale-free model. Based on the construction algorithm of the traditional BA scale-free model, this improved algorithm will introduce threshold of node, inherent attribute of node and the factor of growth of power law of the network, which will improve the node connection probability formula. Making use of the MATLAB to simulate the evolution process of the traditional BA scale-free model and the improved BA scale-free model, compares and analyzes the simulation results of average path length and clustering coefficient of the two models. Choosing the appropriate calculation method to calculate the degree distribution of the two models from the perspective of numerical value, study the simulation of the degree distribution of the two models, simulate and compare robustness and fragility. And this paper simulates and compares the reckless and fragility of the two models when facing random failure and deliberate attacks.In the end, this paper will applies respectively the traditional BA scale-free model and the improved BA scale-free model to the Internet and then simulates the network performance based on the packet loss rate, throughput and delay rate, verifies the improved BA scale-free network for the feasibility and the accuracy of the Internet network simulation.