Secure access to electronic newspaper

Presents and investigates the performance of a secure access scheme to shared information. The primary target application is the electronic newspaper for mobile, wirelessly accessing users. In this application, a dynamically changing set of users is allowed to access the newspaper server. The authors based the solution on the locker key scheme, in which a user´s access permission is granted by the server placing a universal encryption key in the user´s buffer. The newspaper is then encrypted with the universal key and made public. Some of the salient features of the proposed scheme are: the newspaper is encrypted once and a single copy is stored in the server, the encryption is done off-line, considerably reducing the server congestion, and there is no need to redistribute the universal key upon its change. Furthermore, the authors show that, using some realistic parameter values, the scheme can reduce the access time two to three orders of magnitude over a scheme in which the encryption is performed in real-time on a request-by-request basis