Timed Commitments
Authors: D. Boneh and M. Naor
Abstract:
We introduce and construct timed commitment schemes, an
extension to the standard notion of commitments in which
a potential forced opening phase permits the receiver to
recover (with effort) the committed value without the help of the committer.
An important application of our timed-commitment scheme is contract
signing: two mutually suspicious parties wish to
exchange signatures on a contract. We show a two-party protocol
that allows them to exchange RSA or Rabin signatures. The protocol is
strongly fair: if one party quits the protocol early, then the
two parties must invest comparable amounts of time to retrieve the
signatures. This statement holds even if one party has many more machines
than the other. Other applications, including honesty preserving
auctions and collective coin-flipping, are discussed.
Reference:
In proceedings of Crypto '2000, Santa Barbara, LNCS 1880, Springer Verlag, pp. 236--254, 2000
Full paper: PostScript [first posted 10/2000 ]