A New Method of Generating Synchronizable Test Sequences that Detect Output-shifting Faults Based on Multiple UIO Sequences

The objective of testing is to determine the conformance between a system and its specification. When testing distributed systems, the existence of multiple testers brings out the possibility of synchronization problems among remote testers and the possibility that output-shifting faults go undetected. This paper proposes a new method of generating minimal synchronizable test sequences that detect output-shifting faults based on multiple UIO sequences. The procedure of test generation involves two steps: constructing several auxiliary digraphs from a given specification and finding a rural Chinese post tour (RCPT) in the resultant digraph. When constructing the auxiliary digraphs, different from all the former methods, we use vertices to denote transitions and edges to represent two consecutive transitions. In terms of property and application, the proposed method can construct a relatively simple digraph which makes test generation easily. After applying it to practice, we got hold of better results than the existing methods.