Comparing LOTOS and Z re nement relations

This paper compares the LOTOS and Z re nement relations The motivation for such a comparison is the use of multiple viewpoints for specifying complex systems de ned by the reference model of the Open Distributed Processing ODP standard ization initiative The ODP architectural semantics describes the application of formal description techniques FDTs to the speci cation of ODP systems Of the available FDTs Z is likely to be used for at least the information and possibly other viewpoints whilst LOTOS is a strong candidate for use in the computational viewpoint Mechanisms are clearly needed to support the parallel development and integration of view points using these FDTs We compare the LOTOS bisimulation relations and the reduction relations to the Z re nement relation showing that failure traces re nement corresponds closely to re nement in Z