Resource Cost Analysis of Intrusion Tolerance

The resource cost of intrusion tolerance is analyzed quantitatively. The concepts of steady cost and transient cost of intrusion tolerant system are proposed basing on the classification of intrusion tolerant measures. Reference to the computational method of the information entropy in information theory, the computational formula of steady cost is given. The function of the transient cost and the intrusion time is obtained according to the distributive property between the intrusion time and the intrusion probability, and the transient cost is described intuitively through computing its mathematical expectation. Lastly, some characteristics of the transient cost are analyzed through simulation, and some methods and notes of reducing the transient cost are given basing on the analysis result.