Semantic foundations for heterogeneous systems

• Authors: Roberto Passerone;Alberto L. Sangiovanni-Vincentelli
• Venue: Semantic foundations for heterogeneous systems
• Year: 2004

The ability to incorporate increasingly sophisticated functionality makes the design of electronic embedded systems complex. Many factors, beside the traditional considerations of cost and performance, contribute to making the design and the implementation of embedded systems a challenging task. The inevitable interactions of an embedded system with the physical world require that its parts be described by multiple formalisms of heterogeneous nature. Because these formalisms evolved in isolation, system integration becomes particularly problematic. In addition, the computation, often distributed across the infrastructure, is frequently controlled by intricate communication mechanisms. This, and other safety concerns, demand a higher degree of confidence in the correctness of the design that imposes a limit on design productivity. The key to addressing the complexity problem and to achieve substantial productivity gains is a rigorous design methodology that is based on the effective use of decomposition and multiple levels of abstraction. Decomposition relies on models that describe the effect of hierarchically composing different concurrent parts of the system. An abstraction is the relationship between two representations of the same system that expose different levels of detail. To maximize their benefit, these techniques require a semantic foundation that provides the ability to formally describe and relate a wide range of concurrency models. This Dissertation proposes one such semantic foundation in the form of an algebraic framework called Agent Algebra. Agent Algebra is a formal framework that can be used to uniformly present and reason about the characteristics and the properties of the different models of computation used in a design, and about their relationships. This is accomplished by defining an algebra that consists of a set of denotations, called agents, for the elements of a model, and of the main operations that the model provides to compose and to manipulate agents. Different models of computation are constructed as distinct instances of the algebra. However, the framework takes advantage of the common algebraic structure to derive results that apply to all models in the framework, and to relate different models using structure-preserving maps. (Abstract shortened by UMI.)