Strengthening Encryption Secrecy for Private Search Using Fully Homomorphic Encryption

A system for private searching on streaming data, allows client to send the encrypted search query to the remote server. The server uses the encrypted query on a stream of documents and returns the matching documents to the client without revealing the features of the query. A novel technique for private searching on streaming data is proposed which is based on keyword frequency that is the number of times that a keyword appears in the document is required to be higher or lower than a given threshold. This form of query searching can help the client in locating more related documents. Using fully homomorphic encryption techniques, the server can perform search for retrieving the related documents even though the search query is in encrypted form. Our scheme provides number of vital benefits for the client. They provide provable secrecy for encryption, in the view that the untrusted server cannot gather any information about the plaintext. They also reinforce hidden queries, so that the client may ask the remote server to search for a secret word without revealing the word to the server.