Mutation Testing for Rule-Based Verification of Railway Signaling Data

Industry applications of formal verification to signaling control tables require formulation of a large number of mathematical conjectures expressing verification rules. It is paramount to establish the validity and completeness of these conjectures. This article discusses a mutation-based validation technique that guides domain experts in the construction of such verification rules. Furthermore, we use genetic programming to quickly generate millions of well-formed data mutations of control tables and to synthesize mutation programs. The technique is illustrated by a synthetic running example and a discussion of our experience in using it in the industrial setting.