Ad hoc networks was developed in the 2000s, they was highly used in dynamic environment, particularly for inter-vehicular communication (VANETs : Vehicular Ad hoc Networks). Since that time, many researches and developments process was dedicated to VANET networks. These were motivated by the current vehicular industry trend that is leading to a new transport system generation based on the use of new communication technologies in order to provide many services to passengers, the fact that improves the driving and travel's experience. These systems require traffic information sharing and dissemination, such as the alert message emitting, that be exchanged for drivers protection on the road. Sharing such information between vehicles helps to anticipate potentially dangerous situations, as well as planning better routes during congestion situations. The current paper attempts to model and simulate VANET Networks, aiming to analyze and evaluate security information dissemination approaches and mechanisms used in this type of networks in several exchanges conditions. The second objective is to identify their limitations and suggest a new improved approach. This study was conducted as part of our research project entitled "Simulation & VANETs", where we justify and validate our approach using modeling and simulation techniques and tools used in this domain.