| Conformance testing is the detailed, systematic testing of an implementation to ensure that it correctly implements applicable requirements of the specification. This dissertation considers generating tests to be applied in a restricted test environment, where a tester does not have complete control over and observability of the System Under Test (SUT).; Two important problems that frequently arise when testing is performed in a restricted testing environment are studied. The first one, termed the timing constraint problem, results in a methodology to generate a minimum-cost test sequence for a protocol with timers. Due to active timers, the number of consecutive self-loop transitions that can be traversed in a given state before a timeout occurs is limited. A test sequence that does not consider timing constraints will likely be unrealizable in a test laboratory, potentially resulting in either incorrect failing of a valid implementation, or passing an incorrect one. A proposed optimization method generates minimum-length test sequences that take into account timing constraints for FSM models of communication protocols.; The second problem, termed the controllability problem, occurs in an embedded testing environment, where an IUT communicates with multiple entities. Inputs from the entities communicating with the IUT through interfaces “hidden” inside the SUT cannot be directly applied to the IUT. This practical testing restriction severely limits test coverage. This dissertation introduces a graph conversion algorithm for systems where certain inputs can be generated indirectly (semicontrollable inputs). The test sequences obtained from the converted graph fully utilize semicontrollable inputs (where possible) while avoiding the race conditions.; An important engineering component of this dissertation is a practical application of these theoretical results to a real-life protocol-MIL-STD 188-220B. By implementing the methodology presented in this dissertation in software, we were able to generate and deliver test scripts to the Communications-Electronics Command (CECOM), which leads US Army's activities to develop a 188-220B conformance test facility. These tests are free of interruptions due to unexpected timeouts while their coverage of the number of testable transitions increased from approximately 200 to over 700, which represents a coverage of 95% of the transitions defined in the specification. |
