DisCo Toolset - The New Generation

Formal methods have been considered one possible solution to the so-called software crisis. Tools are valuable companions to formal methods: they assist in analysis and understanding of formal speci cations and enable the use of rigorous techniques in industrial projects. In this paper, an overview of the new DisCo toolset is given. DisCo is a formal speci cation method for reactive and distributed systems. It focuses on collective behaviour of objects and provides a re nement mechanism that preserves safety properties. The toolset currently includes a compiler, a graphical animation tool, and a scenario tool for representing execution traces as Message Sequence Charts. A prototype veri cation back-end based on the PVS theorem prover also exists, and a model checking back-end based on Kronos as well as code generation facilities have been planned. In this paper, the operation of the DisCo toolset is illustrated by applying it to an example speci cation describing a simple cash-point service system.