Henning
Pagnia and Felix C. Gärtner: On the
impossibility of fair exchange without a trusted third
party. Technical Report TUD-BS-1999-02, Department of
Computer Science, Darmstadt University of Technology,
Darmstadt, Germany, March 1999.
Abstract
We attempt to formally define 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.
Available as gnuzipped Postscript file.
Felix Gärtner (felix@informatik.tu-darmstadt.de)