Relevant Epidemic Research Of Internet Based On Complex Network

With the fast development of the computer science, scientists found that vast amount of real networks are neither regular networks nor the random networks but a kind which is different from the two mentioned above in statistics characteristics. This kind of net is called complex networks. Physician Watts and Strogatz published a thesis which is of great influence in Nature,1998in which "small world networks", i. e. using the slight probability to change the regular networks will lead to high cluster coefficient and low range, was put forward. The next year physician Barabasi and Albert’s famous thesis in Science explains that many real networks are all exactly or approximately manifest that they obey the space distribution of a power function and are called scale-free networks.One of the ultimate goal of the research on complex networks is to comprehend the dynamics of them, especially to understand the topology of networks, the formation of its functions, the evolutionary process, its critical phase transitions and its dynamics. For instance, the effect of the networks topology has on the information transmission, the control of the jam on the Internet. As for propagation, there are many models, while the wide spread of computer virus on the net can be regarded as a network propagate act that follows a regular pattern. The pattern and speed of transmission of the virus is constantly upgrading in accord with the fast development of the Internet. Some scientists claim that the virus may paralyze the entire Internet in30seconds if without any protective measures. This thesis aims to find its rules and at the same time set some models to study its dynamics in the process.Based on the knowledge of the complex networks as well as the correlation of the networks scale and the cluster coefficient, this thesis studies the general jamming model of the packets transmission on the Internet, and also analyzes the relationship between the jamming amount and the time is According to the knowledge of the virus propagation the SEIR computer virus propagation model in a homogeneous network was also be discussed and analyzed. An conclusion was drawn that in a homogeneous network, if the probability of incubation, transformation, infection is a-0or the ratio of the density of the incubation node at this period against that in the former period E(t)/E(t-1) was no higher than the average point <k>, the infection will decay.In theoretical research "cascade" is called so because the transmission process of an event undergoes the chain reactions, i.e., one generation events induce the next. blackout induced by Disaster and catastrophe are frightening because they happened in such a short time that people completely have no time or ability to react to them. Accordingly, we first classify the cascading phenomena into two categories:the cascading disasters with "Intrinsic Acceleration Mechanisms" that result in large-scale functional failures and the cascading events without "Intrinsic Acceleration Mechanisms" that do not lead to disasters. We present a simplified sandpile model and a heuristic logistic map to show the characteristics and the regular patterns of two categories. Study about this part has been published in Physica A.Finally, to build the Internet transmission model based on the generalized Fibonacci sequence. At the same time, the MATLAB simulation is also used to draw that the critical value of a certain load at certain time t is ω=1,when ω>1, f(t) gains increase, when ω<1,f(t) increases slowly and come approximately to a certain value. From the empirical research proves the existence of the power-law relationship on the number and time of the computers infected the virus and Intrinsic Acceleration Mechanisms. Study about this part has been published in CCCM2010.