Software architectures are a mechanism to make system design knowledge explicit and amenable to use.
They characterize designs in terms of system components and connectors that enable communication between components. The problem is to represent architectural styles in such a way that unambiguous criteria can be stated to decide whether a given design conforms to some style and how a style representation can help to develop concrete architectures. The approach is exemplified on the case-study of a simple biped robot. Three alternative specifications of the robot are developed, one for each architectural style considered. The CADP toolset is used to construct the LTS models for all three specifications.