Privad: Practical Privacy in Online Advertising

Online advertising is a major economic force in the Internet today. Today’s deployments, however, erode privacy and degrade performance as browsers wait for ad networks to deliver ads. We present Privad, a practical private online advertising system. Privad serves ads from the endhost; this is attractive from three standpoints — privacy, profit, and performance. Tracking the user’s profile on their computer and not at a third-party improves privacy. Better targeting and potentially lower operating costs can improve profits. And relying more on the local endhost rather than a distant central third-party improves performance. We have implemented Privad and deployed it on a small scale. This paper focuses on the scalability aspects of Privad. It describes the Privad architecture and protocols, analyzes its scalability characteristics, and presents measurements that substantiate our scalability claims.