Protocol conformance testing using multiple UIO sequences

Automatic generation of conformance test sequences for communication protocols by means of unique input/output (UIO) sequences is addressed. It is shown that if multiple minimum-length UIO sequences are computed for each state of the finite-state-machine (FSM) specification, then the length of the resulting test sequence is significantly reduced without an appreciable increase in the time needed to compute the sequence. An algorithm for assignment of the multiple UIO sequences is given. This algorithm, which is based on network flow, is polynomial in the number of states and transitions of the FSM and is effective in reducing the overall length of the test sequence