Vehicular ad hoc networks (VANET) are an active area for research and development likely to become an integral part of the communication infrastructure of tomorrow. From road safety to recreation applications, a wide range of services are emerging from the rapid technological advances in vehicles sensing, computing, and wireless capabilities. The key issue with respect to those new purposes is the ability of vehicles to disseminate information collected by on-board sensing devices about their surroundings. In this paper, we propose a component-based approach to analyze existing dissemination protocols for VANETs. Our results help better understand the behavior of each component by avoiding the interplays that may result from their combination. We also identify which technical instantiations best fit to different application profiles and environment parameters, while having regard to the resulting performance issues.