Abstract: The current study of survivability of information system is focused on the technique realization of quantitalively analysis and guarantee of survivability in static environments. The survivability is different with various techniqucs in dynamic work conditions,which can be classified into multiple grades according to corresponding capability.Custom needs to pay different service fee at different survivability grade in an information system. At the same time provider must invest considerable money so as to keep a particular survivability grade. An approach has to be proposed urgently, with which the provider can decide whether to promote the survivability grade by his income. A game-theory based model was constructed in this paper by analyzing the action and income of customer and provider who act as the two players. The mixed strategy Nash equilibrium were derived from the model and the strategy for promoting survivability grade was devised, with which the income of provider can be maximized. An experiment was carried out in an information system simulated by 5 survivability grades and the results show that the gamcthcory based approach presenled in the paper is correct and reasonable.

Key words: Information system, Survivability promotion, Game-theory