Understanding mobile agents via a non-interleaving semantics for facile

  • R. Borgia
  • P. Degano
  • C. Priami
  • L. Leth
  • B. Thomsen
Contributed Papers
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1145)


Mobile agents, i.e. pieces of programs that can be sent around networks of computers, are starting to appear on the Internet. Such programs may be seen as an enrichment of traditional distributed computing. Since mobile agents may carry communication links with them as they move across the network, they create very dynamic interconnection structures that can be extremely complex to analyse. In this paper we analyse a fragment of a system based on the mobile agent principle written in the Facile programming language. We propose a Structural Operational Semantics (SOS) for Facile, giving a proved transition system that records encodings of the derivation trees of transitions in their labels. This information allows us to easily recover non-interleaving semantics for Facile by looking only at the labels of transitions. We use the new Facile semantics to debug an agent based system. This example is a scaled down version of a system demonstrated at the European IT Conference Exhibition in Brussels, 1995.


Behaviour Expression Mobile Agent Virtual Node Causal Dependency Agent Base System 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • R. Borgia
    • 1
  • P. Degano
    • 1
  • C. Priami
    • 1
  • L. Leth
    • 2
  • B. Thomsen
    • 2
  1. 1.Dipartimento di InformaticaUniversità di PisaPisaItaly
  2. 2.European Computer-Industry Research CentreMunichGermany

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