A Game Interpretation of Retractable Contracts

  • Franco BarbaneraEmail author
  • Ugo de’ Liguoro
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9686)


In the setting of contract theory, retractable contracts have been defined to formalize binary session protocols where the partners can go back to certain particular synchronization points when the session gets stuck, looking for a successful state, if any.

In the present paper we propose a three-party game-theoretic interpretation of client/server systems of retractable contracts. In particular, we show that a client is retractable-compliant with a server if and only if there exists a winning strategy for a particular player in a game-theoretic model of contracts. Such a player can be looked at as a mediator, driving the choices in the retractable points. We show that winning strategies for the mediator player correspond to orchestrators in a system of orchestrated client/server sessions, and vice versa.


Operational Semantic Winning Strategy Session Type Affectible Action External Choice 
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.



The authors wish to thank Massimo Bartoletti for an insightful discussion, Mariangiola Dezani for her everlasting support and the three anonymous referees for their help in improving the final version of the paper.


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© IFIP International Federation for Information Processing 2016

Authors and Affiliations

  1. 1.Dipartimento di Matematica e InformaticaUniversity of CataniaCataniaItaly
  2. 2.Dipartimento di InformaticaUniversity of TorinoTorinoItaly

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