Abstract not found

We describe a new `real-time' process algebra with simple semantics but considerable expressivepower. It exhibits the advantages of both the `constraint-oriented' and `marker variable' specification styles. The definition extends Milner's CCS, firstly with a simple notion of absolute time added to actions, and then with relative timing expressions which may refer to time markers.

Contents 1. Motivation 2. General concepts 3. Examples 4. Part I: discrete time (a) Background: temporal logic, !-automata, probabilistic programs (b) Summary of problems (c) Verifying TL specifications (d) Verifying automata specifications (e) Conclusions (part I) 5. Part II: dense time (a) Examples (b) Background: GSMPS, timed automata, region graphs, real-time logics (c) Summary of problems (d) Verification procedures (e) Conclusions (part II) Motivation ffl Analyze algorithms with randomization ffl Compute probability of correct (faulty) executions ffl Model and analyze concurrent systems with randomization -- Compute probability of failure under worst possible nondeterminism ffl Express correctness requirements using temporal logics and automata ffl Use standard models for representing probabilistic behaviour: MCs, GSMPs ffl Perfo

In this paper we de ne a Timed Process Algebra for the speci cation and analysis of concurrent systems, where time becomes an important factor to be considered, such as real-time systems. Thus, the language includes some operators on the basis of Timed LOTOS to describe timed behaviours. We have de ned an operational semantics for this language, and for each process we see how to construct a dynamic state graph which captures the reachable states for it, from which we may analyse some properties of interest, such as time reachability.