Observing Reductions in Nominal Calculi Via a Graphical Encoding of Processes

  • Fabio Gadducci
  • Ugo Montanari
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3838)


The paper introduces a novel approach to the synthesis of labelled transition systems for calculi with name mobility. The proposal is based on a graphical encoding: Each process is mapped into a (ranked) graph, such that the denotation is fully abstract with respect to the usual structural congruence (i.e., two processes are equivalent exactly when the corresponding encodings yield the same graph).

Ranked graphs are naturally equipped with a few algebraic operations, and they are proved to form a suitable (bi)category of cospans. Then, as proved by Sassone and Sobocinski, the synthesis mechanism based on relative pushout, originally proposed by Milner and Leifer, can be applied. The resulting labelled transition system has ranked graphs as both states and labels, and it induces on (encodings of) processes an observational equivalence that is reminiscent of early bisimilarity.


Nominal calculi reduction semantics synthesised labelled transition systems relative pushouts graph transformations 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Fabio Gadducci
    • 1
  • Ugo Montanari
    • 1
  1. 1.Dipartimento di InformaticaUniversità di Pisa 

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