Research On Malware Time-delay Propagation Model With A Variable Infection Rate

With the quick development of the Internet and the increase of network complexity, the problem of network security becomes more serious. Due to the fast spread speed, the strong destructive power and the large effective scope of the malware, the problem that how to curb the spread of the malware has become very urgently. The conventional propagation model of the malware usually includes some hypothesis and ignores the network and human factors, so a more accurate propagation model of malware is put up forward, and finding the spread characteristics is meaningful.Through the research into the characteristics and the conventional propagation model of the malware, based on the SIV model, the pulse quarantine based on a hybrid intrusion detection system (IDS) is applied, and the SIQV model based on the pulse quarantine strategy is put up forward. Then the SIQV model is analyzed, especially the stability of its equilibrium point. At the same time the validity of the pulse quarantine strategy is verified by the numerical simulation and experiment.Now there have been some scanning malware methods, including the scanning based on target list, route scanning, divide-and-conquer scanning and so on. The infection rate of using different scanning strategies is different, and even it also varies in the different stage, so a new propagation model of malware based on the variable infection rate is generated. When the new malware arrives, the computer with temporary patch will lose immunity and this course will continues a period of time which is called time delay Based on the two factors above, the delay propagation model of malware based on the variable infection rate is put up forward, that is to say SIQVD model The stability of the model and the switch critical condition is analyzed. The theoretical analysis and numerical simulation indicates the SIQVD model has a delay critical value ?0. When the practical time-delay is lower than it, the system is stable and is easy to control, at the same time the quantity of infected computers decrease notably. However, when the time delay is larger than it, the system will lose stability, and this will induces the spread of malware difficult to control The variable infection rate of the SIQVD is simulated, and the result indicates that we can control the quantity of infected computer in a certain scale by controlling the factors affecting the infection rate. Finally, the propagation model of two kind of malware is tested by simulation. The simulations and the numerical experiments are very identical, and the accuracy of the theoretical analysis and numerical simulation is verified.