Annular Architecture for the Intrusion-Tolerance System

An annular architecture for the intrusion-tolerance system is presented. The data consistency algorithm and control algorithm for servers are described in detail. This system guarantees the data consistency when the total of servers online is more than twice the number of malicious servers, and the performance of intrusion-tolerance can be improved by adjusting the number of servers online dynamically. The system availability is illustrated in the simulation experiments and a time zone of higher availability is also presented.