Electronic Contract Signing Without Using Trusted Third Party

  • Zhiguo WanEmail author
  • Robert H. Deng
  • David Lee
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9408)


Electronic contract signing allows two potentially dis-trustful parties to digitally sign an electronic document “simultaneously” across a network. Existing solutions for electronic contract signing either require the involvement of a trusted third party (TTP), or are complex and expensive in communication and computation. In this paper we propose an electronic contract signing protocol between two parties with the following advantages over existing solutions: 1) it is practical and scalable due to its simplicity and high efficiency; 2) it does not require any trusted third party as the mediator; and 3) it guarantees fairness between the two signing parties. We achieve these properties by employing a trustworthy timestamping service in our protocol, where the timestamping service can be either centralized or decentralized. We also provide a detailed analysis on security and performance of our scheme.


Hash Function Trust Third Party Fair Exchange Honest Party Hash Chain 
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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Sim Kim Boon Institute for Financial EconomicsSingapore Management UniversitySingaporeSingapore
  2. 2.School of Information ScienceSingapore Management UniversitySingaporeSingapore

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