Privacy of Value-Added Context-Aware Service Cloud

In the cloud computing era, service provider cloud and context service cloud store all your personal context data. This is a positive aspect for value-added context-aware service cloud as it makes that context information collection are easier than was the case previously. However, this computing environment does add a series of threats in relation to privacy protection. Whoever receives the context information is able to deduce the status of the owners and, generally owners are not happy to share this information. In this paper, we propose a privacy preserved framework which can be utilized by value-added context-aware service cloud. Context data and related services access privileges are determined by context-aware role-based access control (CRAC) extended from role-based access control (RAC). Privacy preserved context service protocol (PPCS) is designed to protect user privacy from exposed context information. Additionally, user network and information diffusion is combined to evaluate the privacy protection effect.