Ada95 object-oriented and real-time support for development of software fault tolerance reusable components

The paper reports our experience on exploiting the object oriented and real time features of Ada95 to support the development of a reusable software fault tolerance testbed. The testbed is a hardware and software platform for the creation of software fault tolerance systems from reusable components and provides a fault injection environment for evaluating their effectiveness. The reusable components were identified from an in depth analysis of the software fault tolerance domain and designed using an object oriented approach based on the Booch Method. The result of the analysis and design is a set of objects and their communication patterns. The identified objects were classified as active, passive, and shared data objects and implemented as reusable components by mapping them into the corresponding Ada95 object oriented constructs. A distributed recovery block system with a simplified air traffic control application were developed from the reusable components to demonstrate effective reuse and meeting soft real time requirements