...sws@cs.dartmouth.edu}

Initial work was done while the first three authors were at IBM Research in summer, 1999. Later work, including contributions by the fourth author, were sponsered in part by the Defense Advanced Research Projects Agency under DARPA contract N6601-99-28913 (under supervision of the Space and Naval Warfare Systems Center San Diego), by the National Science foundation under grant FD99-79852, and by the United States Postal Service under grant USPS 1025 90-98-C-3513. Views and conclusions contained in this document are those of the authors and do not necessarily represent the official opinion or policies, either expressed or implied of the US government or any of its agencies, DARPA, NSF, USPS.

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...auctions [#Varian95##1#].

There is also a recent case in which a child in Philadelphia placed fraudulent bids in electronic auctions, and won the bid [4].

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...auctioneer

Note that Franklin and Reiter provide a powerful tool to address this problem - they have a system of e-cash where payment is provided automatically to the winner of an auction [5].

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...synchronization,

Smith, Johnson, and Tygar [15]; and Smith [13] contain relevant material on using secure coprocessors for clock synchronization.

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...markets.

It is amusing to note that this same technique also could be used for many more applications: for example, the 2000 US election vote in Florida had many controversies. One was the question of inclusion of votes by military personnel (on ships, for example) who could not postmark their ballots. Secure coprocessor timestamping would help here.

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