Sdl* { an Annotated Speciication Language for Engineering Multimedia Communication Systems

The Speciication and Description Language (SDL) and Message Sequence Charts (MSC) are formal description techniques which gain more and more importance in the development and speciication of complex real-time systems, especially in the telecommunications area. SDL is used to describe the structure and the functional behaviour of a system while MSCs are used to describe its dynamic behaviour. Non-functional aspects such as costs, timing requirements, etc. are not integrated into the speciication process although they are important for the implementation of a real-time system. In order to reeect these important non-functional aspects in the formal speciication, SDL needs to be enhanced with additional features. In this paper we present SDL* { an annotation concept for SDL which allows for the speciication of non-functional aspects.