An Environment for Testing Safety-Critical Protocols

This paper presents an environment for fault injection based testing of protocols that implement fault tolerance and redundancy management in safety-critical distributed realtime systems. Building confidence in the correctness of distributed protocols is an intrinsically difficult problem that requires the use of complementary testing and verification techniques. To this end, we propose a verification approach that involves three steps: i) initial testing in a software simulator, ii) formal verification by model checking and iii) final testing in a hardware prototype. Here, we describe an integrated test environment intended for the first and third steps in the verification process. It allows a tester to expose a protocol to various failure scenarios in both a software simulator and a hardware prototype system. Common data formats for definition of failure scenarios and for storing test results makes it possible to run identical tests in the simulator and the hardware prototype and simplifies comparison of test results.