A Method for Design and Analysis of Next Generation Aircraft Computer Systems

Next generation aircraft computer systems require a major advance in system design practice and associated methods of analysis compared to even the most modern aircraft systems now in service. As well as the ongoing need to demonstrate predictable, real-time behaviour for a wide range of safety critical and mission critical applications, a significant improvement in flexibility is required in order to support cost-effective design-time and in-service modifications to the system. The system design and analysis problem is further complicated by a trend towards increasing functional and physical integration. In this paper, we address the temporal aspects of the problem and propose a design/analysis approach based on resource reservation. This supports top-down development by incorporating only appropriate timing information at each stage of development and deferring the use of implementation details until absolutely necessary. At each stage of refinement, the system model supports localised changes with minimal re-analysis, thus minimising the impact (and associated cost) of such changes.