MHS conformance testing experiences in designing a test suite [message handling]

The process of designing the conformance testing specification manual X.403/CTSM.1 for interpersonal messaging systems is described. This CCITT document was developed by two working groups of the Swiss PTT project. The notation for test-case specification and a number of decisions taken to arrive at this notation are explained. The CTSM.1 manual was used as a reference for the other documents on X.400 conformance testing, the techniques are also valid from the CTSM.2 and CTSM.3 test manuals, concerning conformance testing of message transfer systems and reliable transfer servers, respectively