A Secure and Privacy-Protecting Protocol for Transmitting Personal Information Between Organizations

  • David Chaum
  • Jan-Hendrik Evertse
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 263)


A multi-party cryptographic protocol and a proof of its security are presented. The protocol is based on RSA using a one-way-function. Its participants are individuals and organizations, which are not assumed to trust each other. The protocol implements a “credential mechanism”, which is used to transfer personal information about individuals from one organization to another, while allowing individuals to retain substantial control over such transfers.

It is proved that the privacy of individuals is protected in a way that is optimal against cooperation of all organizations, even if the organizations have infinite computational resources. We introduce a “formal credential mechanism”, based on an “ideal RSA cryptosystem”. It allows individuals a chance of successful cheating that is proved to be exponentially small in the amount of computation required. The new proof techniques used are based on probability theory and number theory and may be of more general applicability.


Execution Process Security Check Message Space Integer Coprime Signature Authority 
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

© Springer-Verlag Berlin Heidelberg 1987

Authors and Affiliations

  • David Chaum
    • 1
  • Jan-Hendrik Evertse
    • 1
  1. 1.Centre for Mathematics and Computer ScienceAmsterdamThe Netherlands

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