Cryptographic Approch for Workflow Systems

  • Yasuo Hatano
  • Kunihiko Miyazaki
  • Toshinobu Kaneko
Conference paper
Part of the IFIP – The International Federation for Information Processing book series (IFIPAICT, volume 286)


This paper proposes encryption schemes to enforce the order of the procedure in a workflow system. In workflow systems, it is important to perform a procedure according to an order that is given by some regulation. In addition, it is desired that each reviewer checks a necessary part of a document to admit the application because the document sometime contains privacy information, e.g., name, birthday, income and so on. There is a procedure in a workflow system which it is sufficient to pass if one of two reviewers admits the document. More generally, there is a procedure in a workflow system that can be passed if k of n reviewers admit the document, which we call a “threshold procedure”. By applying a cryptographic technique, e.g., a multiple encryption and secret sharing, this paper gives a method to realize various procedures in workflow systems, i.e., controlling the order of reviewers, disclosing a part of document selectively, and a threshold procedure. Conventional workflow systems control their procedure by a server, which we consider a trusted one. This implies that an administrator might tamper a procedure. The proposed schemes help us to enforce a procedure even if he/she is not trustworthy.


Encryption Scheme Secret Sharing Decryption Algorithm Basic Construction Credit Facility 
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

© International Federation for Information Processing 2008

Authors and Affiliations

  • Yasuo Hatano
    • 1
  • Kunihiko Miyazaki
    • 1
  • Toshinobu Kaneko
    • 2
  1. 1.Systems Development LaboratoryHitachi, Ltd.Kanagawa-ken
  2. 2.Tokyo University of ScienceChiba-ken

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