On Timed Models and Full Abstraction

In this paper we study a denotational model for a discrete-time version of CSP. We give a compositional semantics for the language. The model records refusal information at the end of each time unit; we believe this model to be simpler than existing models. We also show that the model is fully abstract: equivalence in the model corresponds to the natural equivalence of may testing; and all members of the denotational model are syntactically expressible. We also consider a slightly weaker model, containing no refusal information; we show that this model corresponds to an alternative form of may testing. We briefly discuss the application of these models to the study of information flow in multi-level secure systems.

[1]  Wilson A. Sutherland,et al.  Introduction to Metric and Topological Spaces , 1975 .

[2]  A. W. Roscoe,et al.  The Timed Failures-Stability Model for CSP , 1999, Theor. Comput. Sci..

[3]  Sang Joon Kim,et al.  A Mathematical Theory of Communication , 2006 .

[4]  Willem P. de Roever,et al.  Full abstraction of a real-time denotational semantics for an OCCAM-like language , 1987, POPL '87.

[5]  Joël Ouaknine Discrete analysis of continuous behaviour in real-time concurrent systems , 2000 .

[6]  C. E. SHANNON,et al.  A mathematical theory of communication , 1948, MOCO.

[7]  Iain Phillips,et al.  Refusal Testing , 1986, Theoretical Computer Science.

[8]  Rocco De Nicola,et al.  Testing Equivalences for Processes , 1984, Theor. Comput. Sci..

[9]  C. A. R. Hoare,et al.  Communicating sequential processes , 1978, CACM.

[10]  Ouaknine Joel,et al.  Discrete analysis of continuous behaviour in real-time concurrent systems , 2000 .

[11]  Bernhard Steffen,et al.  Reactive, generative, and stratified models of probabilistic processes , 1990, [1990] Proceedings. Fifth Annual IEEE Symposium on Logic in Computer Science.

[12]  Joël Ouaknine,et al.  Digitisation and Full Abstraction for Dense-Time Model Checking , 2002, TACAS.

[13]  Andrew William Roscoe,et al.  The Theory and Practice of Concurrency , 1997 .

[14]  Steve A. Schneider,et al.  Concurrent and Real-time Systems: The CSP Approach , 1999 .

[15]  Gavin Lowe,et al.  Defining information flow quantity , 2004, J. Comput. Secur..