Secure Rank-ordered Search Of Multi-keyword In Cloud Storage Platform

With the rapid development of cloud storage technology, more and more companies and individuals to select the data stored in cloud storage platform, in order to save the management cost of data. Necessary of protecting privacy part of data is encrypted on the cloud storage platform. So that is inconvenience for users to search the wanted documents. In order to meet the requirements of searching in the encrypted data, there are many related research. But existing search encryption scheme are mostly use vector retrieval model, at the time of retrieval needs a large number of vector product operation and cause retrieval time consuming too much and the cloud storage servers executing the sort algorithm increased security risk. Aiming at the deficiency of the existing scheme, a more safe and retrieval more efficient encryption search mechanism has proposed.First in order to let the cloud storage servers focus on storage, encryption search plug-in system is introduced. The encrypted search plug-in system is responsible for handling the server retrieval request. At the same time data provider execute some sort algorithm will make the results partially transparent, which improve the security. Secondly, in order to improve the retrieval efficiency, reduce dimension of index vector, select document highly representative keywords as index of document, reduces the amount of calculation, when retrieving so as to improve the retrieval efficiency. In addition in order to improve the accuracy of retrieval result for local sorting, when making local sorting the classification algorithm is adopted to document classification which make the accuracy of the retrieved results improved. On the other hand the existing encryption search scheme return the set of docs to user, this requires a lot of network resources. Based on the grouping encryption scheme for document encryption, so that can real-time generate user retrieval related document summary, so send the summary to user and can choose the target document, reduce the waste of network resources. Then on the basis of the proposed search strategy an encryption search plug-in system has been designed.The encryption search scheme proposed in this paper by move the sort algorithm from cloud server to the data provider strengthen the protection of user privacy. In addition by index vector dimension reduction to reduce the amount of calculation, improve the efficiency of retrieval. At last by document classification the accuracy of the result of searching has been guaranteed.