TOGO-generating communication protocol implementations from formal specifications

Abstract

Formal specification techniques (FDTs) are a very important means for system design. The main drawback of such specifications however is the gap between the design of the specification and the development of the implementation. Our aim was to close this gap by providing a tool which transforms a specification written in the FDT LOTOS automatically into an implementation. To ensure a maximum of safety, the transformations must be correct. For our purposes we chose OCCAM as our target language. Because of its closeness to LOTOS we were able to derive a set of provable rules for the implementation generation, which formed the basis of the development of the TOPO compiler. The paper presents a concise overview of the transformation rules as well as the resulting compiler. The more sophisticated rules are discussed in a comprehensive way. The generation of an OCCAM implementation of the branch PROFIBUS of the European fieldbus standard from a formal LOTOS specification, demonstrates the fitness of our solution.