  With the prevalence and development of GNSS technologies, location-based
vehicle services (LBVS) have experienced a rapid growth in recent years.
However, location is a sensitive and private piece of information, so the
design and development of such services just take the clients' privacy concerns
into account. In this paper, we propose a new electronic toll pricing system
based on group signatures, which provides a strong guarantee for the clients'
anonymity within groups. Our system achieves a balance between privacy and the
communication overhead imposed upon the users.
