Experimental evaluation of computer-based railway control systems

Several factors are creating pressure for the enhancement of methodologies and techniques for the validation of computer-based railway control systems. These factors are related to the introduction of new technologies and equipment, the design of interoperable railway networks in Europe, and the new strong competition in the market of railway products. This paper presents LIVE (Low-Intrusion Validation Environment), the validation environment developed at Ansaldo-Cris to experimentally evaluate the dependability of the new families of computer-based railway control systems. The methodological framework for LIVE is summarized. LIVE integrates fault injection and software testing techniques to achieve an accurate and nonintrusive analysis of a system prototype. Such evaluation is needed to ensure full compliance with the new dependability standards emerging for railway apparatus. The test results of a trial application are presented. These results highlight the importance of the quality of the test set and its influence on the final evaluation of system dependability.