Equitable Key Escrow with Limited Time Span (or, How to Enforce Time Expiration Cryptographically) Extended Abstract

  • Mike Burmester
  • Yvo Desmedt
  • Jennifer Seberry
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1514)


With equitable key escrow the control of society over the individual and the control of the individual over society are shared fairly. In particular, the control is limited to specified time periods. We consider two applications: time controlled key escrow and time controlled auctions with closed bids. In the first the individual cannot be targeted outside the period authorized by the court. In the second the individual cannot withhold his closed bid beyond the bidding period. We propose two protocols, one for each application. We do not require the use of tamper-proof devices.

Key Words

key escrow auctions with closed bids time stamps 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Mike Burmester
    • 1
  • Yvo Desmedt
    • 2
    • 1
  • Jennifer Seberry
    • 3
  1. 1.Information Security GroupRoyal Holloway - University of LondonEghamUK
  2. 2.Center for Cryptography, Computer and Network Security, and Department of EE & CSUniversity of Wisconsin - MilwaukeeUSA
  3. 3.Center for Computer Security ResearchUniversity of WollongongAustralia

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