Test Automation for Deterministic Communication Networks Using Chained Orthogonal Arrays

Abstract

arinc 664 is one of the most popular Ethernet-based deterministic network (dtn) technologies for safety-critical avionics systems. A typical arinc 664 network can support several thousands of Virtual Links (vls), each of which has hundreds of thousands of combinations for its configuration. Orthogonal Arrays (oas) method is a formalism to generate a test suite with a feasible size and a desired coverage of features for complex systems. Since the test space for dtn features is prohibitively large, a single application of oas may inadvertently eliminate many combinations of two-way interactions. In this paper, we propose to develop a test automation system that uses multiple and consecutive applications of oas to generate test configurations for dtn. The test factors representing dtn configuration parameters are divided into two groups, where the first group includes the number of vls passing through each port while the second group includes the configuration parameters for vls. Then, oas are constructed sequentially for each group such that an output element of the first oa is used as one of the inputs for the second oa. We present a system architecture for a test automation system capable of verifying real-time network operations, where the outputs of the chained oas are utilized to generate executable test scripts including dtn configurations and traffics. As a case study, a test automation system is successfully implemented for arinc 664switch. Note to Practitioners—Safety-critical avionics networks with a large number of configuration parameters need to be tested rigorously. Exhaustive testing of all possible configurations is not realistic since there are time and resource constraints. Therefore, a chained orthogonal array is proposed to create different sub-configuration spaces of the test parameters for dtn. An automation system is mandatory to generate the repeatable test cases fast and make them simpler to implement and run. In this article, a test automation system from generating the test cases using the chained orthogonal arrays to carrying out the tests on the prototype system is presented. We believe that the concepts presented in this article can be utilized by other researchers developing a test automation for complex systems having a large number of parameters.