Typing Mobility in the Seal Calculus

  • Giuseppe Castagna
  • Giorgio Ghelli
  • Francesco Zappa Nardelli
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2154)


The issue of this work is how to type mobility, in the sense that we tackle the problem of typing not only mobile agents but also their movement. This yields higher-order types for agents. To that end we first provide a new definition of the Seal Calculus that gets rid of existing inessential features while preserving the distinctive characteristics of the Seal model. Then we discuss the use of interfaces to type agents and define the type system. This type system induces a new interpretation of the types: interfaces describe interaction effects rather than, as it is customary, provided services. We discuss at length the difference of the two interpretations and justify our choice of the former.


Type System Mobile Agent Typing Rule Mobility Attribute Subtyping Relation 
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 2001

Authors and Affiliations

  • Giuseppe Castagna
    • 1
  • Giorgio Ghelli
    • 2
  • Francesco Zappa Nardelli
    • 1
    • 2
  1. 1.c.n.r.s., D’epartement d’Informatique’Ecole Normale Sup’erieureParisFrance
  2. 2.Dipartimento di InformaticaUniversit’a di PisaPisaItaly

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