Cooperative vehicular systems are being developed to improve traffic safety and efficiency through the dynamic exchange of information between vehicles and between vehicles and infrastructure units. Different communication protocols and policies have been proposed in the literature with diverse objectives, normally taking into account network performance metrics only. This paper illustrates the need of taking into account cooperative vehicular application requirements in the design and operation of cooperative vehicular protocols, such as congestion control protocols. The results obtained demonstrate the impact of the application requirements on the communication settings of each vehicle, and on the overall channel load generated.