The Impact of Context Information on User Privacy in Social Networks

Context-aware applications are becoming very popular as they are a mean of enriching users' experiences in multimedia scenarios. Nevertheless, the acquisition, representation, and protection of contextual information are still open issues that need to be addressed. These are significant topics of interest mainly due to today's growing concern on user privacy, and are particularly relevant in the context of Social Networks. In this paper, we briefly present our work development within the Visnet-II Network of Excellence (NoE) on context acquisition and protection for context-based content adaptation. We identify the sensitive contextual information used within Social Network application scenario, and then specify a suitable privacy model. Finally, we describe how this model could be implemented through the use of the MPEG-21 Rights Expression Language (REL) Standard.