Assuring Standard Conformance of Partial Interfaces

A current standardization effort for track-side equipment in German railways faces the difficulty of having to proceed incrementally. This means that only some of the interfaces of complex entities like interlocking controllers are specified while others remain under the control of the diverse manufacturers. As these other interfaces are necessary for testing the specified ones for standard conformance, a specific approach has to be devised to be able to achieve this goal. This paper presents the problem in its practical setting and the way it is intended to be solved