More robust private information retrieval scheme

In e-commerce, the protection of users' privacy from a server was not considered feasible until the private information retrieval (PIR) problem was stated and solved. A PIR scheme allows a user to retrieve a data item from an online database while hiding the identity of the item from a database server. In this paper, a new PIR scheme using a secure coprocessor (SC) and including mutual authentication by DSA signature algorithm for protecting the privacy of users, is proposed. Because of using only one server and including the mutual authentication process in the proposed scheme, it is more efficient and more robust (secure) in the real e-commerce environment compared with previous PIR solutions. In addition, a security analysis (proof) for the proposed scheme and comparisons to other PIR schemes are given.