FAST: An Efficient Decision Procedure for Deduction and Static Equivalence

Message deducibility and static equivalence are central problems in symbolic security protocol analysis. We present Fast, an efficient decision procedure for these problems under subtermconvergent equational theories. Fast is a C++ implementation of an improved version of the algorithm presented in our previous work [10]. This algorithm has a better asymptotic complexity than other algorithms implemented by existing tools for the same task, and Fast’s optimizations further improve these complexity results. We describe here the main ideas of our implementation and compare its performance with competing tools. The results show that our implementation is significantly faster: for many examples, Fast terminates in under a second, whereas other tools take several minutes.