tailieunhanh - Privacy for the Stock Market

With Nokia’s planned move to Windows Phone as its primary smartphone platform, Symbian becomes a franchise platform, leveraging previous investments to harvest additional value. This strategy recognizes the opportunity to retain and transition the installed base of 200 million Symbian owners. Nokia expects to sell approximately 150 million more Symbian devices in the years to come. Under the new strategy, MeeGo becomes an open-source, mobile operating system project. MeeGo will place increased emphasis on longer-term market exploration of next-generation devices, platforms and user experiences. Nokia still plans to ship a MeeGo-related product later this year. . | Privacy for the Stock Market Giovanni Di Crescenzo Telcordia Technologies Inc. 445 South Street Morristown NJ 07960 giovanni@ Abstract. We investigate the problem of performing Stock Market operations such as buying or selling shares of a certain stock in a private way which had recently been left open. We present a formal definition for a private stock purchase protocol addressing several privacy and security concerns on usual on-line stock market operations. According to our definition a client would not reveal how many shares she is buying or selling not even which of these two cases is happening and what price she is offering for those. We then present an efficient protocol meeting this definition based on the hardness of the decisional Diffie-Hellman problem. Our protocol requires no interaction between the clients can be executed in a constant number of rounds between the clients and the server and requires several technical contributions such as a new and efficient zero-knowledge protocol for proving sum-related statements about encrypted values which is of independent interest. 1 Introduction The overwhelming expansion of the internet is today being accompanied with a large increase of financial activities and transactions that are conducted online. A few minutes navigation on the internet allows to realize the existence of electronic cash systems pyyment protocols and ions lotteries digital casinos and gambing systems. The sometimes crucial importance and often large interest around such transactions raises several concerns about the security and the privacy of the information that users and organizations are willing to use on a network. In this paper we consider a important financial transaction buying and selling shares of a particular stock on the Stock Market. Such transactions seem to have received not enough attention from the security and privacy literature and in fact an assessment of the privacy problems deriving from these .