Poster: Towards secure spectrum auction: Both bids and bidder locations matter

Truthful spectrum auctions make bidders reveal their true valuations for spectrum to maximize their utilities. However, disclosure of one's true value causes numerous security vulnerabilities. Moreover, as a distinguished property of spectrum auction compared to classical auctions, spectrum reutilisation requires that the bidder locations be disclosed to the auctioneer to run the auction. We investigate the impact of disclosing bidder locations and demonstrate that such disclosure can be exploited by a malicious auctioneer to gain extra profit and significantly degrade bidders' utility. We then design a provably secure spectrum auction framework that does not leak any information on either bids or bidder locations other than the auction outcome. Technically, we leverage tools in garbled circuits and secret sharing, and design data-oblivious algorithms where the execution path does not depend on the input. We further implement our solution and theoretically and experimentally show that it incurs only limited computation and communication overhead.