1. Introduction
Urban Computing (UrbComp) is an extension of ubiquitous computing (Ubicomp) 1. Similar to Ubicomp, the
main goal of UrbComp is to allow the users access to embedded services in the infrastructure or the Web at any
time and at any place2. However, the surroundings of UrbComp are denser in terms of the number of users, bigger
with regard to the physical factor, and more diverse as relates to types of users and social groups3. Microsoft
Research also defines Urban Computing as an acquisition process, analysis and integration of huge volumes of
data which are heterogeneous in nature, due to the fact that they are generated by the diversity of sources in urban
spaces such as sensors, devices, spaces, vehicles, buildings and people, to face the main problems big cities deal
with. One of the major challenges big cities have to deal with is security. Crime fighting is one of the main tasks