Timed verification with μCRL

μCRL is a process algebraic language for specification and verification of distributed systems. μCRL allows to describe temporal properties of distributed systems but it has no explicit reference to time. In this work we propose a manner of introducing discrete time without extending the language. The semantics of discrete time we use makes it possible to reduce the time progress problem to the diagnostics of "no action is enabled" situations. The synchronous nature of the language facilitates the task. We show some experimental verification results obtained on a timed communication protocol

Serializability preserving extensions of concurrency control protocols

The verification system PVS is used to obtain mechanized support for the formal specification and verification of concurrency control protocols, concentrating on database applications. A method to verify conflict serializability has been formulated in PVS and proved to be sound and complete with the interactive proof checker of this tool. The method has been used to verify a few basic protocols. Next we present a systematic way to extend these protocols with new actions and control information. We show that if such an extension satisfies a few simple correctness conditions, the new protocol is serializable by construction