Towards Personal Privacy Control Susana Alcalde Bag¨ u´ es 1, 2 , Andreas Zeidler 1 , Carlos Fernandez Valdivielso 2 , and Ignacio R. Matias 2 1 Siemens AG, Corporate Research and Technologies Munich, Germany 2 Public University of Navarra Department of Electrical and Electronic Engineering Navarra, Spain {susana.alcalde.ext,a.zeidler}@siemens.com {carlos.fernandez,natxo}@unavarra.es Abstract. In this paper we address the realization of personal privacy control in pervasive computing. We argue that personal privacy demands differ substantially from those assumed in enterprise privacy control. This is demonstrated by intro- ducing seven requirements specific for personal privacy, which are then used for the definition of our privacy policy language, called SenTry. It is designed to take into account the expected level of privacy from the perspective of the individual when interacting with context-aware services. SenTry serves as the base for im- plementing personal privacy in our User-centric Privacy Framework for pervasive computing. 1 Introduction Privacy is a prime concern in today’s information society where personal sensitive data has to be revealed in common daily tasks. Thus, laws exist that shall control the col- lection and processing of sensitive information and should prevent its misuse by en- terprises. Individuals, though, often are not really aware of personal privacy issues and mostly make decisions casually or on the move. Even in open settings, like the Internet, users control privacy mostly manually and are limited to acknowledging some prefab- ricated privacy statements. To our believes, for the upcoming era of so-called Ambient intelligence [1], which fosters the deployment of heterogeneous Context-Aware Mobile Services (CAMS), such habitual control of personal privacy eventually will fall short. The large number of services alone will make a manual per-use authorization of access to personal data (as required by law) an impossible task. Personal privacy is a more “intimate” concern than the enterprise’s requirement to meet existing legislations. The challenge is to meet the individual’s expected level of privacy when information is revealed to third parties. In this paper, we focus on man- aging personal privacy “offline”, e.g., beforehand of actually being in a particular situa- tion. To do so, we have elaborated requirements for personal privacy control and applied them in the design of the SenTry language, which allows users to generate appropriate User Privacy Policies to automatically govern all accesses to their sensitive data. The SenTry language is presented in this paper as a centerpiece of our ongoing work, focused in the development of the User-centric Privacy Framework (UCPF) [2]. The R. Meersman, Z. Tari, P. Herrero et al. (Eds.): OTM 2007 Ws, Part II, LNCS 4806, pp. 886–895, 2007. c  Springer-Verlag Berlin Heidelberg 2007