Dependability and Performance Evaluation of Intrusion-Tolerant Server Architectures

In this work, we present a first effort at quantitatively comparing the strengths and limitations of various intrusion-tolerant server architectures. We study four representative architectures, and use stochastic models to quantify the costs and benefits of each from both the performance and dependability perspectives. We present results characterizing throughput and availability, the effectiveness of architectural defense mechanisms, and the impact of the performance versus dependability tradeoff. We believe that the results of this evaluation will help system architects to make informed choices for building more secure and survivable server systems.