Conformance testing methodologies for OSI protocols

As open systems interconnection (OSI) protocol standards mature and systems are developed to implement them, facilities to test protocol implementations for conformity to relevant international standards and recommendations are becoming the key to vendor interoperability. This paper examines the test methods applicable to OSI conformance testing as defined by the International Organization for Standardization (ISO) and the International Telegraph and Telephone Consultative Committee (CCITT). The advantages and disadvantages of each test method are discussed. Each test method is analyzed in terms of its technique in providing synchronization between the test system and the system under test (SUT), and its ability to supply a controlled environment for comprehensive protocol testing. We also discuss the applicability of each test method to different OSI protocols, and the generic aspects oftest system architecture common to all test methods. Specific attention is paid to those test methods that will be used to test X.25 implementations and network management protocols.