The use of inter-vehicle communication is considered the next step to be taken in order to reduce the number of traffic accidents. The design of a versatile and efficient protocol that would manage the access to the control channel reserved for safety applications would represent a significant progress towards a generally accepted technology. However, the solutions proposed hitherto rarely took into account the broadcast nature of the messages produced by the safety applications. Furthermore, the specific properties of periodic vehicular beaconing are yet to be considered by any technical committee or research study. We present the specificities of this type of messages and discuss their impact on the performance of the medium access control layer, using both analytical and simulation tools.