Jim Woodcock, Susan Stepney, David Cooper, John A. Clark, Jeremy L. Jacob.
The certification of the Mondex electronic purse to ITSEC Level E6.

Formal Aspects of Computing 20(1):5-19, 2008

Abstract:

Ten years ago the Mondex electronic purse was certified to ITSEC Level E6, the highest level of assurance for secure systems. This involved building formal models in the Z notation, linking them with refinement, and proving that they correctly implement the required security properties. The work has been revived recently as a pilot project for the international Grand Challenge in Verified Software. This paper records the history of the original project and gives an overview of the formal models and proofs used.

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@article(SS-FACS-08,
  author = "Jim Woodcock and Susan Stepney and David Cooper
           and John A. Clark and Jeremy L. Jacob",
  title = "The certification of the {M}ondex electronic purse to {ITSEC} Level {E6}",
  journal  = "Formal Aspects of Computing",
  volume = 20,
  number = 1,
  pages = "5--19",
  year = 2008
)