• Corpus ID: 11671049

On the Impossibility of Fair Exchange without a Trusted Third Party

  title={On the Impossibility of Fair Exchange without a Trusted Third Party},
  author={Henning Pagnia and Felix C. Gartner Darmstadt},
We attempt to formally deene the strong fair exchange problem and present a proof that it is impossible to solve strong fair exchange without a trusted third party. The proof is established by relating strong fair exchange to the problem of consensus and adapting the impossibility result of Fischer, Lynch and Paterson. We show that strong fair exchange is at least as hard as consensus and explore a few requirements for trusted third parties in order to be of use in fair exchange. Impossibility… 

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  • N. Asokan
  • Computer Science
    Research report / RZ / IBM / IBM Research Division / Zürich Research Laboratory
  • 1998
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