Dependability is an increasingly critical charactreristic of the Navy's mission critical computer systems. These systems must be maintained in a state of readiness to support critical mission function s, and must be able to perform these functions correctly despite the presence of faultsd in system components, and in the environments in which the systems operate. Automated tools are needed to assist in specifying andf evaluating dependability characteristics of Navy computer system designs, and in balancing dependabilikty against other system attributes such as performance, security, and cost. Phase I reseach demonstrated the feasibility of an automated system dependability assessment tool (SDAT) for assessment of mission critical computer system dependability. Phase II will develop a full operational prototype SDAT. The prototype SDAT will consist of a dependability specification component, that allows interactive creation and manipulation of system design representations, and a dependability evaluation component, that automatically translates system design descriptions into mathematical models, and computers a range of quantitative dependability metrics. Phase II will also produce integration technologies that will allow SDAT to interoperate with other Navy information models and system engineering tools, and a series of examples that will validate the utility and SDAT for dependability assessment of actual Navy systems.
Benefit: The proposed dependability assessment tool will be of immediate benefit in the development of complex mission critical computer systems. System engineers will use SDAT during the design phase to ensure that system dependability goals are met, while reducing development costs and operational ridsks. Potential areas of commercial application include design evaluation of systems supporting process control, commercial avionics, and on-line transaction processing.
Keywords: System Design apture, Reliability Prediction Tools, Mission Reliability, System Design Capture, Dependability Specification, Fault Toleratnt System Design, Fault-Tolerant System Design, System Maintainability, Dependability Evaluation, Operational Availability