An object-oriented design methodology for distributed services

Due to the highly increasing complexity of new telecommunication services and the distributed nature of them on the one hand and the requirement to come up with a short time to market on the other hand, new methods, techniques and tools covering the whole service development process are needed. The paper presents an integrated approach covering the fields of designing, validating and testing services and reusable service components. Therefore, a methodology which applies concepts from the Reference Model for Open Distributed Processing (ODP) is introduced. As an important part to bridge the gap from the design plane to the implementation plane, a language mapping from ODL to C++ is described. ODL is an extension of CORBA-IDL and allows one to specify objects with multiple interfaces. A CORBA based environment is assumed to be the execution platform. To ensure that the service to be designed meets the requirements of a potential user, a validation stage has been included in the design methodology. Therefore an (abstract) behavior description based on a formal language is needed and provided by a combination of ODL and SDL. After the validation of the SDL model, abstract TTCN test cases are derived from it semi-automatically. The paper also contains a new method for automated testing of distributed services through executing these test cases in a CORBA based target environment.