Title | Verification of clock synchronization algorithms: experiments on a combination of deductive tools |
Publication Type | Journal Article |
Year of Publication | 2007 |
Authors | Barsotti, D, Nieto, LP, Tiu, A |
Journal | Formal Asp. Comput. |
Volume | 19 |
Pagination | 321-341 |
Abstract | We report on an experiment in combining the theorem prover Isabelle with automatic first-order arithmetic provers to increase automation on the verification of distributed protocols. As a case study for the experiment we verify several averaging clock synchronization algorithms. We present a formalization of Schneider’s generalized clock synchronization protocol [Sch87] in Isabelle/HOL. Then, we verify that the convergence functions used in two clock synchronization algorithms, namely, the Interactive Convergence Algorithm (ICA) of Lamport and Melliar-Smith [LMS85] and the Fault-tolerant Midpoint algorithm of Lundelius–Lynch [LL84], satisfy Schneider’s general conditions for correctness. The proofs are completely formalized in Isabelle/HOL. We identify parts of the proofs which are not fully automatically proven by Isabelle built-in tactics and show that these proofs can be handled by automatic first-order provers with support for arithmetics. |
DOI | 10.1007/s00165-007-0027-6 |