Study On Survivability Evaluation Based On Timed Automata

Along with the informatization of the modern society,network information system plays an important role in the daily life.The security of the network information system has been improved by the traditional security measures,but all kinds of attacks,failures and emergencies incessant occurred.Survivability can keep the essential services and basic attributes of the system after being attacked.It is must for survivability to consider problems about the security of the network information system and it is a very important research problem of how to evaluate and improve the survivability of the system.The purpose of the evaluation of the survivability is to analyze the system,evaluate its survivability,measure the system's ability of providing services in the unsafe environment,provide the information of survivability of the system and improve the survivability of the system.Firstly,some concepts for the survivability and survivability evaluation are introduced such as the definition of the survivability,the difference and relationship of the related concepts of survivability,the method of evaluating the system's survivability and the trend of research trend,then proposes a framework to evaluate the survivability of the information system.The framework includes the concepts of the survivability of the system,requirement analysis of the survivability,measurement of the survivability,quantitative analysis and generate the analysis report,mainly introduced a survivability quantization method.With the advantage of time automaton model for describing time constraints,time automaton model for the system is build and the transferring from infinite states to finite states is done by discretizing the time variable,then the real time response ability combining with K path algorithm for the essential services to evaluate the survivability of the information system is quantized.The feasibility and effectiveness for the given evaluating method are verified by simulation.Finally,the work in this paper is summarized,and research plans for next step is also pointed out.