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The book was inadvertently published with an incorrect name of the copyright holder. The name of the copyright holder for this book is: © IFIP International Federation for Information Processing. The book has been updated with the changes.

Conformiq Qtronic is a commercial tool for model driven testing. It derives tests automatically from behavioral system models. These are black-box tests [1] by nature, which means that they depend on the model and the interfaces of the system under test, but not on the internal structure (e.g. source code) of the implementation.

In this essay, which accompanies my invited talk, I survey the nature of Conformiq Qtronic, the main implementation challenges that we have encountered and how we have approached them.

Fault management, including fault detection and location, is an important task in management of Web Services. Fault detection can be performed through testing, which can be active or passive. Based on passive observation of interactions between a Web Service and its client, a passive tester tries to detect possible misbehaviors in requests and/or responses. Passive observation is performed in two steps: passive homing and fault detection. In FSM-based observers, the homing consists of state recognition. However, it consists of state recognition and variables initialization in EFSM-based observers. In this paper, we present a novel approach to speed up homing of EFSM-based observers designed for observation of Web Services. Our approach is based on combining observed events and backward walks in the EFSM model to recognize states and appropriately initialize variables. We present different algorithms and illustrate the procedure through an example where faults would not be detected unless backward walks are considered.

In this paper we present an automatic testing process to validate Avionic Systems. To do that, we have developed a tool that interprets scripts written in Automated Test Language and translate them to user codes written in C language. To carry out this work, the syntax of scripts has been defined by a context free grammar. This testing process is based on the execution of a pre-defined set of test cases. Currently, these test sets are obtained from Test Description Document and they are introduced in the system in C code manually. Therefore, automation of this process would reduce the time used for the testing, as a great quantity of tests are realized and a great quantity of errors are made when tests are made by hand.

This paper adresses the generation of test cases for testing the conformance of a reactive black-box implementation with respect to its specification. We aim at extending the principles and algorithms of model-based testing for recursive interprocedural specifications that can be modeled by Push-Down Systems (PDS). Such specifications may be more compact than non-recursive ones and are more expressive.

The generated test cases are selected according to a test purpose, a (set of) scenario of interest that one wants to observe during test execution. The test generation method we propose in this paper is based on program transformations and a coreachability analysis, which allows to decide whether and how the test purpose can still be satisfied. However, despite the possibility to perform an exact analysis, the inability of test cases to inspect their own stack prevents it from using fully the coreachability information. We discuss this partial observation problem, its consequences, and how to minimize its impact.

Interoperability testing aims at verifying the possibility for two or more components to communicate correctly while providing the foreseen services. In this paper, we describe a new method for generating interoperability test cases. This method is equivalent to classical methods in terms of non-interoperability detection. Contrary to classical approaches, this method avoids the well-known state-space explosion problem. It has been implemented in the CADP Toolbox and applied to a simplified version of the ISDN connection protocol. The obtained results confirm the real contribution of this method: test cases has been derived while classical approaches face the state-space explosion problem.

The interrelationship between software faults and failures is quite intricate and obtaining a meaningful characterization of it would definitely help the testing community in deciding on efficient and effective test strategies. Towards this objective, we have investigated and classified failures observed in a large complex telecommunication industry middleware system during 2003- 2006. In this paper, we describe the process used in our study for tracking faults from failures along with the details of failure data. We present the distribution and frequency of the failures along with some interesting findings unravelled while analyzing the origins of these failures. Firstly, though “simple” faults happen, together they account for only less than 10%. The majority of faults come from either missing code or path, or superfluous code, which are all faults that manifest themselves for the first time at integration/system level; not at component level. These faults are more frequent in the early versions of the software, and could very well be attributed to the difficulties in comprehending and specifying the context (and adjacent code) and its dependencies well enough, in a large complex system with time to market pressures. This exposes the limitations of component testing in such complex systems and underlines the need for allocating more resources for higher level integration and system testing.

In a component oriented approach, components are designed, developed and validated in order to be widely used. However one cannot always foresee which specific uses will be made of components depending on the system they will constitute. In this paper we propose an approach to test each component of a system by extracting accurate behaviours using information given by the system specification. System specifications are defined as input/output symbolic transition systems structured by a communication operator (synchronized product) and an encapsulation operator (hiding communication channels). By projecting symbolic execution of a system on its components, we derive unitary symbolic behaviours to be used as test purposes at the component level. In practice, those behaviours can be seen as typical behaviours of the component in the context of the system. We will illustrate on an example that those behaviours could not have been extracted by reasoning uniquely at the component level.

We present a testing framework using a compositional approach to generate and execute test cases. Test cases are generated and combined with respect to a partial specification expressed as a set of requirements and elementary test cases. These approach and framework are supported by a prototype tool presented here. The framework is presented here in its LTL-like application, besides other specification formalisms can be added.

In this paper we present a new approach to test the conformance of a wireless ad hoc routing protocol. This approach is based on a formal specification of the DSR protocol described by using the SDL language. Test scenarios are automatically generated by a tool developed in our laboratory. A method enabling to execute them on an implementation into a real network is illustrated. Indeed, an important issue is to execute some generated test scenarios on a dynamic network in which the links are routinely modified. Therefore, the concept of self-similarity is presented to reduce the number of nodes by collapsing them in a real network. This enables to execute the test scenarios in defining a relationship between the network and specification topologies.