Verifying Privacy Preserving Combinatorial Auctions

<p>Suppose you are competing in an online sealed bid auction for some goods. How do you know the auction result can be trusted? The auction site could be performing actions that support its own commercial interests by blocking certain bidders or even reporting incorrect winning prices. This problem is magnified when the auctioneer is an unknown party and the auctions are for high value items. The incentive for the auctioneer to cheat can be high as they could stand to make a significant profit by inflating winning prices or by being paid by a certain bidder to announce them the winner. Verification of auction results provides confidence in the auction result by making it computationally infeasible for an auction participant to cheat and not get caught. This thesis examines the construction of verifiable privacy preserving combinatorial auction protocols. Two verifiable privacy preserving combinatorial auction protocols are produced by extending existing auction protocols.</p>

Verifying Privacy Preserving Combinatorial Auctions

<p>Suppose you are competing in an online sealed bid auction for some goods. How do you know the auction result can be trusted? The auction site could be performing actions that support its own commercial interests by blocking certain bidders or even reporting incorrect winning prices. This problem is magnified when the auctioneer is an unknown party and the auctions are for high value items. The incentive for the auctioneer to cheat can be high as they could stand to make a significant profit by inflating winning prices or by being paid by a certain bidder to announce them the winner. Verification of auction results provides confidence in the auction result by making it computationally infeasible for an auction participant to cheat and not get caught. This thesis examines the construction of verifiable privacy preserving combinatorial auction protocols. Two verifiable privacy preserving combinatorial auction protocols are produced by extending existing auction protocols.</p>

Anonymous Sealed-Bid Auction on Ethereum

In a competitive market, online auction systems enable optimal trading of digital products and services. Bidders can participate in existing blockchain-based auctions while protecting the confidentiality of their bids in a decentralized, transparent, secure, and auditable manner. However, in a competitive market, parties would prefer not to disclose their interests to competitors, and to remain anonymous during auctions. In this paper, we firstly analyze the specific requirements for blockchain-based anonymous fair auctions. We present a formal model tailored to study auction systems that facilitate anonymity, as well as a generic protocol for achieving bid confidentiality and bidder anonymity using existing cryptographic primitives such as designated verifier ring signature. We demonstrate that it is secure using the security model we presented. Towards the end, we demonstrate through extensive simulation results on Ethereum blockchain that the proposed protocol is practical and has minimal associated overhead. Furthermore, we discuss the complexity and vulnerabilities that a blockchain environment might introduce during implementation.

A First-Price Sealed-Bid Asymmetric Auction When Two Bidders Have Respective CRRA and General Utility Functions

We study a first-price auction with two bidders where one bidder is characterized by a constant relative risk aversion utility function (i.e., a concave power function) while the other has a general concave utility function. We establish the existence and uniqueness of the optimal strategic markups and analyze the effects of one bidder’s risk aversion level on the optimal strategic markups of him and his opponent’s, the allocative efficiency of the auction, and the seller’s expected revenue, respectively.