Abstract of /TIGKI/INFOSYS/FKI/FKI-245-02
Title: Secure and Private Auctions without Auctioneers
Authors: Felix Brandt
Revision-Date: Februar 2002
Category: Technical Report (Forschungsberichte Künstliche Intelligenz)
Abstract: Security and privacy have become crucial factors in auction
design. Various schemes to ensure the safe conduction of
sealed-bid auctions have been proposed recently. We introduce
a new standard of security for auctions (``full privacy''),
that prevents extraction of bid information despite any
collusion of participants. This requirement is stronger than
other common assumptions that prohibit the collusion of
certain third-parties (e.g., distinct auctioneers). Full
privacy is obtained by distributing shares of each bid on
all bidders. The bidders then jointly compute the selling
price without uncovering any additional information.
Auctioneers are obsolete in these ``bidder-resolved''
auction protocols. The auction outcome cannot be changed by
dishonest bidders; they can only inhibit the protocol. For
this reason, we present a sub-protocol that detects
dishonest bidders, so that they can be fined, which
provides the incentive to follow the main protocol.
The major contribution of this work is the fully private
Vickrey auction protocol that determines the second-highest
bid without revealing any other information. As full
privacy is our main goal, the drawback of our protocol
is efficiency. For this reason, it is currently only
applicable for high-security auctions with relatively
few bidders in reasonable time.
Keywords: agents, auctions, cryptography
Size: 15 pages
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