Research Of Malwares' Cooperation Propagation Model Through Removable Storage Media Restraining Strategy In Isolation Network

Nowadays,with the deeper integration of industrialization and information,industrial safety problem is becoming more and more serious.The traditional concept that host in isolation network is safe has been subverted.The most important part of industrial control system's threat is all kinds of malware damage.The malware not only spread through network but also through removable storage media on account of the spread of malware is more and more complicated.Besides,different malware will cooperate in the process of spreading.The traditional propagation model is difficult to analyze the characteristics when considering the cooperation between worm and virus.Therefore,it's really an urgent problem that how to describe the propagation of malware through removable storage media in isolation network and how to constrain the cooperation between malwares.Malware is hard to penetrate into the industrial control system because hosts in industrial control system is the network isolation.So the malware spreading through the removable storage media will cause great damage to the industrial control system.During its spread process,one malware is infected by another one and then spread together.Thus forms the phenomena of these two malware cooperating with each other,which is known as cooperation.This paper mainly considers the cooperation between worm and virus because it's complex when two malware work together.This thesis concerns the cooperation of virus and worm.They can spread through the removable media is also concerned.We proposes a propagation model named SIwIvwV based on this two characteristics.We find that removable storage media plays an important role in the spread of malware through the analysis.Furthermore,in order to constrain the propagation of the worm and virus,we constructs a propagation model named SIwIvwSV.In addition,we establish the complete system with the immunization,kill to constrain the propagation of worm and virus.This paper takes theoretical analysis for these two established propagation models of the malware,analyzes the stability of the systems,deduces the stable condition of the systems remaining stable.Through numerical analysis,we make valid certification for that these two models can describe the behavior of malware propagation through network and removable storage media in the isolated network.At the same time,it also analyze effectiveness of the restraining strategies from different aspects.Finally,we carry on the discrete time simulation experiments by these two propagation models.By analysis of simulation curve and numerical curves,we find that the two curves could be fitted very well.And this shows that the correctness of the theoretical derivation and numerical simulation.