INTERNATIONAL JOURNAL OF RESEARCH IN COMPUTER APPLICATIONS AND ROBOTICS www.ijrcar.com Vol.3 Issue 9, Pg.: 92-97 September 2015 R.SHENBAGAVALLI, M.KANIMOZHI, P.GEETHA Page 92 INTERNATIONAL JOURNAL OF RESEARCH IN COMPUTER APPLICATIONS AND ROBOTICS ISSN 2320-7345 PRIVACY PRESERVING MULTI KEYWORD RANKED SEARCH OVER ENCRYPTED DATA 1 R.SHENBAGAVALLI, 2 M.KANIMOZHI, 3 P.GEETHA 1 Associate Professor in Krishnasamy College of Engineering and Technology, Cuddalore, Tamilnadu. E-mail id: shenbagasuresh@gmail.com 2 M.E in Krishnasamy College of Engineering And Technology, Cuddalore, Tamilnadu. E-mail id: kani071092@gmail.com 3 M.E in Krishnasamy College of Engineering And Technology, Cuddalore, Tamilnadu. E-mail id: geethaparthy@gmail.com Abstract: - With the advent of cloud computing, data owners are motivated to outsource their complex data management systems from local sites to the commercial public cloud for great flexibility and economic savings. But for protecting data privacy, sensitive data have to be encrypted before outsourcing, which obsoletes traditional data utilization based on plaintext keyword search. Thus, enabling an encrypted cloud data search service is of paramount importance. In this project, for the first time, to define and solve the challenging problem of privacy-preserving Multi-keyword Ranked Search over Encrypted data (MRSE) in cloud computing, and to establish a set of strict privacy requirements for such a secure cloud data utilization system. Among various multi-keyword semantics, and to choose the efficient similarity measure of “coordinate matching,” i.e., as many matches as possible, to capture the relevance of data documents to the search query. Further use “inner product similarity” to quantitatively evaluate such similarity measure. In this project first to propose a basic idea for the MRSE based on secure inner product computation, and then give two significantly improved MRSE schemes to achieve various stringent privacy requirements in two different threat models. To improve search experience of the data search service, further extend the two schemes to support more search semantics. Extensive performance evaluations have shown that the proposed scheme can achieve better efficiency in terms of the functionality and computation overhead compared with existing ones. For the future work, to investigate on the authentication and access control issues in searchable encryption technique. Key terms: MRSE, Blind Storage, Index F 1. INTRODUCTION Mobile cloud computing gets rid of the hardware limitation of mobile devices by exploring the scalable and virtualized cloud storage and computing resources, and accordingly is able to provide much more powerful and scalable mobile services to users. In mobile cloud computing, mobile users typically outsource their data to external cloud servers, e.g., iCloud, to enjoy a stable, low-cost and scalable way for data storage and access. However, as