The research activities of the "Critical Information Systems" (Systèmes Informatiques Critiques - SINC) area focus on the design and analysis of complex systems that have to satisfy strong properties imposed by critical applications. These properties are expressed by a set of, potentially conflicting, requirements defined in terms of temporal constraints, quality of service, dependability, fault tolerance and cooperative operation. The related design methodology will thus have to manage, as early as possible in the life cycle, all these constraints and ensure that such requirements can be satisfied by the implemented system.

The activities conducted within this area and that motivate its designation are: the definition, the exploitation and the tooling of methods and techniques, both formal and experimental, for designing, assessing, developing and managing complex and critical software-intensive systems.

The SINC area federates the work of the groups Software Tools for Communication (OLC), Dependable Computing and Fault Tolerance (TSF), System Engineering and Integration (ISI), and Distributed Computing and Asynchronism (CDA), whose research activities concern respectively:

The design of communication protocols and services for the emerging network technologies and the new Internet generation in order to support advanced distributed, high performance, multimedia and cooperative applications, as well as the study of formal techniques for describing and verifying critical systems.
The dependability of computer systems, defined as the property allowing the users of a system to place a justified confidence in the service that it delivers them, that encompasses the attributes of availability, reliability, integrity, confidentiality, maintainability, safety and security.
The engineering of systems, emphasizing the integration of models following three complementary directions: the modeling of heterogeneous systems, the integration of models in requirement engineering and in design activities, and the simulation and co-simulation of complex systems.
The distribution and asynchronism in computing, and more specifically asynchronous algorithms suitable for networking context. The privileged environments concern the implementation of distributed peer-to-peer computations. In this domain, the effort concerns also self-organizational issues in the domain of widely deployed interactive systems.

More specifically, the research issues addressed within the SINC area concerns in particular:

The architecture of the system and of its specifications, including its various functions and all their interactions.
The formal description of its behaviors, both in terms of functional and non functional properties (i.e., according to temporal, performance and dependability constraints), the formal expression of the requirements identified during the design, their verification or their evaluation, the tooling of the formal description and verification techniques and their integration in the industrial development process;
The implementation and the control on target environments of the development chain from the implementation phase up to the operational phase.
The real-time simulation and the distributed co-simulation of systems and systems of systems.
The evaluation via stochastic modeling, via metrology in nominal or disrupted environments, and via the analysis and the characterization of the observed behaviors.
Networks and distributed systems, with their functional, topological and compositional aspects, encompassing different levels: i) the basic concepts and their analysis, ii) the architectures supporting communication and cooperation and, iii) the high performance processing of computation intensive applications on either dedicated or generic architectures.
The resilience of computer-based systems with respect a wide spectrum of threats, including physical failures, software errors and intrusions, both in terms of architectures and algorithms for fault tolerance, and in terms of verification, testing, and analytical and experimental evaluation.
The definition of security policies and supporting models respecting the principles of privacy, in particular, minimization and control of personal data.
Ubiquitous computing, according to various viewpoints: interactions among the systems that compose the global system, mobility of the users, of the devices and of the services, etc.

The categories of systems being considered are extensive. They range from embedded processing systems, notably for transport and space applications, up to the distributed computing infrastructures underlying the provision of critical services, such as the distribution of electrical energy or air traffic control, and including also the wired or wireless communication networks. These works find further developments within numerous international or national cooperative projects. As such, we can mention the coordination of the network of excellence Resilience for Survivability in IST (ReSIST) of the 6th EU Framework Programme for Research and Technological Development and the numerous contributions in the competitiveness clusters: Aerospace Valley and System@tic.

The themes addressed in the SINC area are also articulated with the activities aimed at the characterization and the realization of computer systems, that are being carried out in several other groups at LAAS, notably on:

the monitoring and management of the resources for the optimization of computer grids;
the hierarchical monitoring and control of the behaviors of autonomous robots;
the design of microsystems and of SoCs (Systems on Chip) focusing on the specification and virtual prototyping levels;
the formal description of architectures and the diagnosis of application-oriented services.