The metric analogue of weak bisimulation for probabilistic processes

J. Desharnais1, R. Jagadeesan2, V. Gupta3, P. Panangaden4
1Département dE28099Informatique, Université Laval, QUE, Canada
2Department of Computer Science, Loyola University Lake Shore Campus, Chicago, IL, USA
3Stratify, Inc., Mountain View, CA, USA
4School of Computer Science, McGill University, Montreal, Que., Canada

Tóm tắt

We observe that equivalence is not a robust concept in the presence of numerical information - such as probabilities-in the model. We develop a metric analogue of weak bisimulation in the spirit of our earlier work on metric analogues for strong bisimulation. We give a fixed point characterization of the metric. This makes available conductive reasoning principles and allows us to prove metric analogues of the usual algebraic laws for process combinators. We also show that quantitative properties of interest are continuous with respect to the metric, which says that if two processes are close in the metric then observable quantitative properties of interest are indeed close. As an important example of this we show that nearby processes have nearby channel capacities - a quantitative measure of their propensity to leak information.

Từ khóa

#Computer science #Probability distribution #Robustness #Channel capacity #Concurrent computing #Distributed computing #Stochastic systems #State-space methods #Logic #Boolean functions

Tài liệu tham khảo

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