Emmanuel Gaudin

The interest in pragmatic analysis methods is constantly fueled by the increasing complexity of software systems. Although the methods are not scarce, to apply them successfully an additional expertise is required, which often deviates from the development process or the domain the system is intended for. The model-driven paradigm facilitates the development and analysis by means of automation. It can address the issue at a certain extent by raising the level of abstraction closer to the… Voir plus

The interest in pragmatic analysis methods is constantly fueled by the increasing complexity of software systems. Although the methods are not scarce, to apply them successfully an additional expertise is required, which often deviates from the development process or the domain the system is intended for. The model-driven paradigm facilitates the development and analysis by means of automation. It can address the issue at a certain extent by raising the level of abstraction closer to the domain. The inherent complexity is shifted from the model towards the automation process. This has been quite effective in handling functional aspects, but non-functional aspects like performance have proven to be challenging in this regard. In this paper we present a model-driven approach for performance analysis based on standardized languages. SDL is used to capture the functional aspects of the system, which are further enriched with performance annotations. Deployment diagrams allow for the available resources to be assigned to system components, and model execution is driven by real test cases in TTCN-3. Automatic execution of different scenarios and graphical presentation of the results can aid the user to optimize performance by choosing the best allocation of resources in terms of execution time and payload. Voir moins

Models in the railway industry are often based on synchronous technologies such as Matlab or Scade. This is due to technical reasons, but because of its concepts the abstraction level of synchronous models are very low and very close to the implementation level. A serious gap is observed between the requirements described in natural textual language and the model which is basically an implementation. The increasing level of system complexity, combining communicating subsystems, calls for a more… Voir plus

Models in the railway industry are often based on synchronous technologies such as Matlab or Scade. This is due to technical reasons, but because of its concepts the abstraction level of synchronous models are very low and very close to the implementation level. A serious gap is observed between the requirements described in natural textual language and the model which is basically an implementation. The increasing level of system complexity, combining communicating subsystems, calls for a more abstract model. This paper will first discuss why synchronous technologies have been used in this type of systems, then an experiment of using an asynchronous technologies on a real ERTMS case coming from SNCF is described, and finally the paper will conclude on how an asynchronous modeling technologies could make the link between the informal textual requirements and the implementation of the system. Voir moins

The constantly ever-growing interest for large-scale distributed systems like the Internet of Things imposes many challenges for developers and researchers from many areas. The development of distributed software applications is by no means trivial, and their inherent complexity becomes apparent during testing. Indeed, testing the operation of single isolated nodes does not suffice, because it may be affected by the distribution
and inter-communication between nodes. Re-writing a test case… Voir plus

The constantly ever-growing interest for large-scale distributed systems like the Internet of Things imposes many challenges for developers and researchers from many areas. The development of distributed software applications is by no means trivial, and their inherent complexity becomes apparent during testing. Indeed, testing the operation of single isolated nodes does not suffice, because it may be affected by the distribution
and inter-communication between nodes. Re-writing a test case to consider distribution is neither efficient nor simple, because concurrency is never easy to implement. In this paper we present an approach that automatically interleaves execution of test cases to simulate concurrency inherent in distribution. We
focus on independent test cases that might exhibit a correlation due to distributed interaction. The approach is applied in the context of standard modeling and testing languages, and enables identification of interaction points during test case execution that depend on distribution. The re-execution of the test case is then
interleaved at the identified points to account for distribution. Voir moins

The Internet of Things (IoT) refers to the networked interconnection of objects equipped with ubiquitous intelligence, or simply “smart objects”. The “smart” part is often followed by words like grid, home, parking, etc., to identify the application domain, and it is provided by software applications and/or services running on top of these large-scale distributed communication infrastructures. Heterogeneity and distribution scale speak for the complexity of such systems and call for a careful… Voir plus

The Internet of Things (IoT) refers to the networked interconnection of objects equipped with ubiquitous intelligence, or simply “smart objects”. The “smart” part is often followed by words like grid, home, parking, etc., to identify the application domain, and it is provided by software applications and/or services running on top of these large-scale distributed communication infrastructures. Heterogeneity and distribution scale speak for the complexity of such systems and call for a careful analysis prior to any deployment on target environments. In this paper we introduce a model-driven approach for the analysis of IoT applications via simulation. Standard modeling languages, code generation, and network simulation and visualization are combined into an integrated development environment for rapid and automated analysis. Voir moins

Specific modelling technologies for digital hardware design are typically the synthesizable, cycle-accurate register-transfer level descriptions (VHDL or Verilog RTL) or bit-accurate transaction level models (SystemC TLM). Given nowadays complexity of circuits such as System-on-a-Chip (SoC) for multimedia embedded systems, and of the embedded software interacting with the SoC, there is a need for a higher abstraction level that would ease mastering the interaction, starting from initial… Voir plus

Specific modelling technologies for digital hardware design are typically the synthesizable, cycle-accurate register-transfer level descriptions (VHDL or Verilog RTL) or bit-accurate transaction level models (SystemC TLM). Given nowadays complexity of circuits such as System-on-a-Chip (SoC) for multimedia embedded systems, and of the embedded software interacting with the SoC, there is a need for a higher abstraction level that would ease mastering the interaction, starting from initial conceptual stages of a product development. The Specification and Description Language (SDL) modelling technology allows to describe functional models independently from their implementation. This paper describes a work done by STMicroelectronics and PragmaDev to experiment the use of SDL high level functional description in a typical simple hardware/ software interaction scenario involving interrupts handling. Voir moins

Interconnected smart devices constitute a large and rapidly growing element of the contemporary Internet. A smart thing can be as simple as a web-enabled device that collects and transmits sensor data to a repository for analysis, or as complex as a web-enabled system to monitor and manage a smart home. Smart things present marvellous opportunities, but when they participate in complex systems, they challenge our ability to manage risk and ensure reliability.

SDL, the ITU Standard… Voir plus

Interconnected smart devices constitute a large and rapidly growing element of the contemporary Internet. A smart thing can be as simple as a web-enabled device that collects and transmits sensor data to a repository for analysis, or as complex as a web-enabled system to monitor and manage a smart home. Smart things present marvellous opportunities, but when they participate in complex systems, they challenge our ability to manage risk and ensure reliability.

SDL, the ITU Standard Specification and Description Language, provides many advantages for modelling and simulating communicating agents – such as smart things – before they are deployed. The potential for SDL to enhance reliability and safety is explored with respect to existing smart things below.

But SDL must advance if it is to become the language of choice for developing the next generation of smart things. In particular, it must target emerging IoT platforms, it must support simulation of interactions between pre-existing smart things and new smart things, and it must facilitate deployment of large numbers of similar things. Moreover, awareness of the potential benefits of SDL must be raised if those benefits are to be realized in the current and future Internet of Things. Voir moins

The objective of the PragmaList Lab, a joint laboratory between PragmaDev and CEA LIST, is to integrate the test generation tool DIVERSITY in the SDL modeling environment Real Time Developer Studio (RTDS). The resulting environment aims to extend RTDS with a Model-Based Testing approach. After briefly describing the characteristics of RTDS and DIVERSITY, this paper presents the work done to integrate these two environments. Then, it highlights the main principles of DIVERSITY based on symbolic… Voir plus

The objective of the PragmaList Lab, a joint laboratory between PragmaDev and CEA LIST, is to integrate the test generation tool DIVERSITY in the SDL modeling environment Real Time Developer Studio (RTDS). The resulting environment aims to extend RTDS with a Model-Based Testing approach. After briefly describing the characteristics of RTDS and DIVERSITY, this paper presents the work done to integrate these two environments. Then, it highlights the main principles of DIVERSITY based on symbolic execution, which enables the generation of test cases in TTCN-3 format. The paper then presents the existing coverage criteria in the integrated generation of test cases. It concludes with the open strategy of the PragmaList approach to work together with industrial actors based on the definition and integration of new specific coverage criteria consistent with their validation constraints. Voir moins

The translation of a system model to an intermediate format is an important step towards formal proofs of properties. This paper presents the formulation of rules to enable the translation of SDL standard models to Fiacre language. The translated model is then provided as input to a suitable toolset that performs model checking and other analysis. The formulated translation rules are discussed in view of the correctness of translation and ease of implementation. Implementations of some of the… Voir plus

The translation of a system model to an intermediate format is an important step towards formal proofs of properties. This paper presents the formulation of rules to enable the translation of SDL standard models to Fiacre language. The translated model is then provided as input to a suitable toolset that performs model checking and other analysis. The formulated translation rules are discussed in view of the correctness of translation and ease of implementation. Implementations of some of the translation rules in an industrial tool (PragmaDev RTDS), and a proof of the concept on a simple SDL model are presented to ascertain the validity of the proposed translation. Voir moins

In the development process the very first phase focuses on the requirements. Most of the requirements are dynamic and describe how the system reacts to a set of stimuli. Not all the possible reactions are listed in the requirements but some mandatory reactions are described that can be seen as properties. Later in the development process is a real system or a representative model of the future system. At that point it is possible to gather execution traces of the real system. Based on the work… Voir plus

In the development process the very first phase focuses on the requirements. Most of the requirements are dynamic and describe how the system reacts to a set of stimuli. Not all the possible reactions are listed in the requirements but some mandatory reactions are described that can be seen as properties. Later in the development process is a real system or a representative model of the future system. At that point it is possible to gather execution traces of the real system. Based on the work of the European PRESTO project this paper describes the work that has been done to use the same kind of model in both cases and match one against the other. Voir moins