Research On Privacy-Preserving Queries And Authentication

This paper applies the data encryption technology and the data authentication technique in the database system. The existing mechanism of database encryption and authentication is analyzed, and the queries and the authentication technique of the encrypted data thoroughly are discussed in order to perfect the database encryption and the confirmation mechanism. So it can guarantee the information security demand nowadays in the network database system.Based on the collection and analysis of large quantity of literatures about security database and especially about database encryption in recent years, firstly, the background about database security is introduced, and the importance of database encryption is pointed out, then the encrypting technology is described. And then, the noticeable issues are analyzed while databases are encrypted, and how to take proper choices is also argued while implementing database encryption.Next, the storage and queries over the encrypted character data in database is mainly studied. A uniform way of the storage and encryption to data is analyzed, and the encryption relational scheme is presented, based on which we give means of Privacy-Preserving Queries on encrypted data. In relate to the encrypted character data in database, firstly, two kinds of ways extracting the characteristic values of the character data are introduced and their safety performance is discussed. One of the ways is based on the Pair- Coding function; the other way is base on the Flatten- Scrambling function. Secondly, encryption storage and Privacy-Preserving Queries method base on the Flatten- Scrambling function are presented. Lastly, the mechanism of the character match inquiry and the relational algebra is studied. Regarding the numerical data, this article analyzes the query way based on the metadata, and improve the storage way. Range queries of the numerical data is realized, which is kept in Privacy-Preserving form.In the database authentication aspect, the demands of database authentication are analyzed. With encryption relational scheme proposed in this paper, an approach of field-based authentication on record is proposed. This approach is safer than the field-based authentication approach, and reserves its flexibility and efficiency.