Privacy preserving personalized access control service at third service provider

With the convenient connection to network, more and more individual information including sensitive information, such as contact list in Mobile Phone or PDA, can be delegated to the professional third service provider to manage and maintain. The benefit of this paradigm is, on one hand to avoid the sensitive information leakage when individual devices failed or lost, on the other hand to make only the authorized users access and share the delegated information online anytime and anywhere. However, in this paradigm the critical problems to be resolved are to guarantee both the privacy of delegated individual information and the privacy of authorized users, and what is more important to afford the owners of communication devices to have high level of control and power to create their own particular access control policies. In this paper, we present an approach to implement the personalized access control at third service provider in a privacy preserving way. Our approach implements the critical problems above in this paradigm by using selective encryption, blind signature and the combination of role based access control and discretionary access control.