The ETSI Test Description Language TDL and its application

The wide-scale introduction of model-based testing techniques in an industrial context faces many obstacles. One of the obstacles is the existing methodology gap between informally described test purposes and formally defined test descriptions used as the starting point for test automation. The provision of an explicit test description becomes increasingly essential when integrating complex, distributed systems and providing support for conformance and interoperability tests of such systems. The upcoming ETSI standard on the Test Definition Language (TDL) covers this gap. It allows describing scenarios on a higher abstraction level than programming or scripting languages. Furthermore, TDL can be used as an intermediate representation of tests generated from other sources, e.g. simulators, test case generators, or logs from previous test runs. TDL is based on a meta-modelling approach that expresses its abstract syntax. Deploying this design approach, individual concrete syntaxes of TDL can be designed for different application domains. The paper provides an overview of TDL and discusses its application on a use case from the rail domain.