Checking states and transitions of a set of communicating finite state machines

Given a model M , consisting of communicating finite state machines (CFSMs), that represents the required behaviour of an implementation I, it is important to test I against M . This paper considers part of the testing process: checking the transition structure of I against that of M . One possible approach, to checking the transition structure of I, is to generate the product machine from M and then test the global transitions using standard finite state machine test techniques. This approach may, however, suffer from a combinatorial explosion. Instead, this paper introduces approaches that may allow local states and transitions of I to be checked without the generation of the product machine. The paper then considers the extension of these approaches to the checking of global states.