TPL: A Trust Policy Language

  • Sebastian MödersheimEmail author
  • Anders Schlichtkrull
  • Georg Wagner
  • Stefan More
  • Lukas Alber
Conference paper
Part of the IFIP Advances in Information and Communication Technology book series (IFIPAICT, volume 563)


We present TPL, a Trust Policy Language and Trust Management System. It is built around the qualities of modularity, declarativity, expressive power, formal precision, and accountability. The modularity means that TPL is built in a way that makes it easily adaptable to different types of transactions and signatures. From the aspect of declarativity and expressive power, the language is built such that policies are always formulated in a positive form and the language is Turing complete. The formal precision and accountability of the language eliminates ambiguity and allows us to achieve verified evaluations. The idea is that for any decision, the system can generate a proof that can then be checked by a prover that is formally verified, in Isabelle/HOL, to be sound with respect to a first-order logic semantics.



Andreas Viktor Hess suggested many improvements.


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Copyright information

© IFIP International Federation for Information Processing 2019

Authors and Affiliations

  • Sebastian Mödersheim
    • 1
    Email author
  • Anders Schlichtkrull
    • 1
  • Georg Wagner
    • 2
  • Stefan More
    • 2
  • Lukas Alber
    • 2
  1. 1.DTU Compute, Formal MethodsTechnical University of DenmarkKongens LyngbyDenmark
  2. 2.Institute for Applied Information Processing and Communications (IAIK)Graz University of TechnologyGrazAustria

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