Analysis of Concurrent Moving Target Defenses

While Moving Target Defenses (MTDs) have been increasingly recognized as a promising direction for cyber security, quantifying the effects of MTDs remains mostly an open problem. Each MTD has its own set of advantages and disadvantages. No single MTD provides an effective defense against the entire range of possible threats. One of the challenges facing MTD quantification efforts is predicting the cumulative effect of implementing multiple MTDs. We present a scenario where two MTDs are deployed in an experimental testbed created to model a realistic use case. This is followed by a probabilistic analysis of the effectiveness of both MTDs against a multi-step attack, along with the MTDs' impact on availability to legitimate users. Our work is essential to providing decision makers with the knowledge to make informed choices regarding cyber defense.