Cloud computing as an emerging technology trend is expected to reshape the advances in information technology. In a costefficient cloud environment, a user can tolerate a certain degree of delay while retrieving information from the cloud to reduce costs. In this paper, we address two fundamental issues in such an environment privacy and efficiency. We first review a private keywordbased file retrieval scheme that was originally proposed by Ostrovsky. Their scheme allows a user to retrieve files of interest from an untrusted server without leaking any information. The main drawback is that it will cause a heavy querying overhead incurred on the cloud, and thus goes against the original intention of cost efficiency. In this paper, we present a scheme, termed efficient information retrieval for ranked query (EIRQ), based on an aggregation and distribution layer (ADL), to reduce querying overhead incurred on the cloud. In EIRQ, queries are classified into multiple ranks, where a higher ranked query can retrieve a higher percentage of matched files. And we can add further enhancement in this paper like we need to use rankings for all the data in the cloud, and based on that rankings user searches should be displayed in the pattern like items having highest ratings will arrives first.
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