Further Results on Architectures and Dependability Mechanisms for Dependable SoSs

Introduction This document reports recent results of work package on architecture and design related to architecture descriptions and design of dependability mechanisms for dependable systems of systems (SoSs), and to systems of systems integration. These results contribute further in the achieving the ultimate work package aim of delivering the definition of an environment for the construction of dependable SoSs out of autonomous heterogeneous systems and dependability mechanisms assisting in building such systems. The deliverable extends further mechanisms and techniques presented in Project deliverable IC2 on Initial Results on Architectures and Dependability Mechanisms for Dependable SoSs. Development of the Conceptual Model (cf deliverable IC1: Revised Version of the Conceptual Model) has had a strong influence on the advances in work package on SoS architecture and design which are reported here. The document is organised into three chapters and an Appendix. These chapters may be read independently, and corresponding bibliographical references are given separately at the end of the report. The first chapter proposes a structured approach to integrating complex Web applications that are built using existing Web services as the component systems. The next part of the deliverable puts forward a general framework for dealing with on-line upgrades of component systems at the level of linking interfaces (LIFs). The last chapter introduces an approach to detecting component system errors at the level of LIFs and to recovering after them, and demonstrates this approach using a real-time microkernel as a component system. A brief overview of the chapter contents is as follows: • Dependable Composition of Web Services: This chapter introduces Project work towards supporting the development of dependable SoSs in the context of the Web Service Architecture. Our approach primarily lies in developing WSCAL (Web Service Composition Action Language) – an XML-based language for the abstract specification of the dependable composition of Web Services, which builds upon the CA Actions concept