Modelling and Proof of a Tree-Structured File System in Event-B and Rodin

  • Kriangsak Damchoom
  • Michael Butler
  • Jean-Raymond Abrial
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5256)


Event-B is a formalism used for specifying and reasoning about complex discrete systems. The Rodin platform is a new tool for specification, refinement and proof in Event-B. In this paper, we present a verified model of a tree-structured file system which was carried out using Event-B and the Rodin platform. The model is focused on basic functionalities affecting the tree structure including create, copy, delete and move. This work is aimed at constructing a clear and accurate model with all proof obligations discharged. While constructing the model of a file system, we begin with an abstract model of a file system and subsequently refine it by adding more details through refinement steps. We have found that careful formulation of invariants and useful theorems that can be reused for discharging similar proof obligations make models simpler and easier to prove.


File system Tree structure Refinement Proof Event-B Rodin tool 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Kriangsak Damchoom
    • 1
  • Michael Butler
    • 1
  • Jean-Raymond Abrial
    • 2
  1. 1.University of SouthamptonUnited Kingdom
  2. 2.ETH ZurichSwitzerland

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