A practical strategy for testing pair-wise coverage of network interfaces

Distributed systems consist of a number of network elements that interact with each other. As the number of network elements and interchangeable components for each network element increases, the trade off that the system tester faces is the thoroughness of test configuration coverage, versus limited resources of time and expense that are available. An approach to resolving this trade off is to determine a set of test configurations that test each pair-wise combination of network components. This goal gives a well-defined level of test coverage, with a reduced number of system configurations. To select such a set of test configurations, we show how to apply the method of orthogonal Latin squares, from the design of balanced statistical experiments. Since the theoretical treatment assumes constraints that may not be satisfied in practice, we then show how to adapt this approach to realistic application constraints.