Thanks to the dynamic and decentralized nature of their infrastructure, Mobile Ad-hoc networks (MANET) contribute significantly to the deployment of services in pervasive environments. In the small area environments (houses, workplaces, hotspots, public areas, etc), these networks are not completely as secure as expected, according to user privacy. Within this kind of environment, it is still a challenging task to provide user authentication, without revealing the identity and/or the location of the communicating nodes. In this paper, we propose a new protocol aiming to preserve user anonymity while providing authentication and secure routing among users within small area networks