Abstract: Cloud computing, is also known as on-demand computing, and provides services to customers over the internet. It serves users by allowing them to store and access data from cloud server at anytime, anywhere, using any devices. Users upload their private data on to the cloud which has to be kept a secret. For such secure information storage many go for encryption approach before outsourcing to cloud. An efficient search scheme needs to be used in order to search data over the encrypted cloud. While having a large number of data users, and documents on the cloud, it is essential to give multi-keywords in the search query to get documents only relevant to these keywords in a ranked order. Coordinate matching and inner product similarity are the multi-keyword concepts used to get the relation between the documents and search queries and similarity measures, respectively.

Keywords: Cloud computing, multi-keyword, data privacy, inner product similarity, coordinate matching.