Vehicular ad-hoc networks with inter-vehicular communications are a prospective technology which contributes to safer and more efficient roads and offers information and entertainment services to mobile users. Since large real-world testbeds are not feasible, research on vehicular ad-hoc networks depends mainly on simulations. Therefore, it is crucial that realistic mobility models are employed. We propose a generic and modular mobility simulation framework (GMSF). GMSF simplifies the design of new mobility models and their evaluation. Besides, new functionalities can be easily added. GMSF also propose new vehicular mobility models, GIS-based mobility models. These models are based on highly detailed road maps from a geographic information system (GIS) and realistic microscopic behaviors (car-following and traffic lights management). We perform an extensive comparison of our new GIS-based mobility models with popular mobility models (Random Waypoint, Manhattan) and realistic vehicular...