Scalable compositional verification of high-level real-time concurrent systems from 10/sup 7/ to 10/sup 85/ states

A compositional CTL mode-checking algorithm for real-time concurrent systems with a discrete global clock is presented based on a new high-level description model. We implement the algorithm in a system called VERIFAST-2 which has passed the extended General Session Setup Control protocols with concurrency from 5 to 51 threads all in one minute and demonstrated truly scalable performance with respect to the size of concurrency. In this respect, it outperforms HyTech version 1.02 b and VERIFAST-1. Then we discuss how to incorporate R.J. Parikh's classic work on semilinear expressions to verify software recursions.