CommitCoin: Carbon Dating Commitments with Bitcoin

(Short Paper)
  • Jeremy Clark
  • Aleksander Essex
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7397)


In the standard definition of a commitment scheme, the sender commits to a message and immediately sends the commitment to the recipient interested in it. However the sender may not always know at the time of commitment who will become interested in it. Further, when the interested party does emerge, it could be critical to establish when the commitment was made. Employing a proof of work protocol at commitment time will later allow anyone to “carbon date” when the commitment was made, approximately, without trusting any external parties. We present CommitCoin, an instantiation of this approach that harnesses the existing computational power of the Bitcoin peer-to-peer network; a network used to mint and trade digital cash.


Commitment Scheme Random Oracle Model Municipal Election Hash Chain Carbon Date 
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 2012

Authors and Affiliations

  • Jeremy Clark
    • 1
  • Aleksander Essex
    • 2
  1. 1.Carleton UniversityCanada
  2. 2.University of WaterlooCanada

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