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FOCUS Research team

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Overall Objectives

Ubiquitous Computing refers to the situation in which computing facilities are embedded or integrated into everyday objects and activities. Networks are large-scale, including both hardware devices and software agents. The systems are highly mobile and dynamic: programs or devices may move and often execute in networks owned and operated by others; new devices or software pieces may be added; the operating environment or the software requirements may change. The systems are also heterogeneous and open: the pieces that form a system may be quite different from each other, built by different people or industries, even using different infrastructures or programming languages; the constituents of a system only have a partial knowledge of the overall system, and may only know, or be aware of, a subset of the entities that operate on the system.

A prominent recent phenomenon in Computer Science is the emerging of interaction and communication as key architectural and programming concepts. This is especially visible in ubiquitous systems. Complex distributed systems are being thought of and designed as structured composition of computational units, usually referred to as components. These components are supposed to interact with each other and such interactions are supposed to be orchestrated into conversations and dialogues. In the remainder, we will write CBUS for Component-Based Ubiquitous Systems.

In CBUS, the systems are complex. In the same way as for complex systems in other disciplines, such as physics, economics, biology, so in CBUS theories are needed that allow us to understand the systems, design or program them, analyze them.

Focus investigates the semantic foundations for CBUS. The foundations are intended as instrumental to formalizing and verifying important computational properties of the systems, as well as to proposing linguistic constructs for them. Prototypes are developed to test the implementability and usability of the models and the techniques. Throughout our work, `interaction' and 'component' are central concepts.

The members of the project have a solid experience in algebraic and logical models of computation, and related techniques, and this is the basis for our study of ubiquitous systems. The use of foundational models inevitably leads to opportunities for developing the foundational models themselves, with particular interest for issues of expressiveness and for the transplant of concepts or techniques from a model to another one.