Conditional E-Cash

  • Larry Shi
  • Bogdan Carbunar
  • Radu Sion
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4886)


We introduce a novel conditional e-cash protocol allowing future anonymous cashing of bank-issued e-money only upon the satisfaction of an agreed-upon public condition. Payers are able to remunerate payees for services that depend on future, yet to be determined outcomes of events. Once payment complete, any double-spending attempt by the payer will reveal its identity; no double-spending by the payee is possible. Payers can not be linked to payees or to ongoing or past transactions. The flow of cash within the system is thus both correct and anonymous. We discuss several applications of conditional e-cash including online trading of financial securities, prediction markets, and betting systems.


Blind Signature Prediction Market Anonymous Communication Payment Protocol Online Trading 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Larry Shi
    • 2
  • Bogdan Carbunar
    • 2
  • Radu Sion
    • 1
  1. 1.Network Security and Applied Cryptography Lab Computer ScienceStony Brook UniversityUSA
  2. 2.Pervasive Platforms and ArchitecturesMotorola LabsUSA

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