GeoNetworking is a protocol specially designed to provide geographical addressing and forwarding for Intelligent Transport Systems (ITS). Unlike advanced messages defined in GeoNetworking, beaconing messages are fundamental to periodically advertise essential information, e.g., a vehicle ITS station's geographical position and speed, to neighbor ITS stations. The beaconing messages should be delivered in a secure manner. Otherwise, geographical addressing and forwarding of GeoNetworking cannot be supported as unauthorized actions from attackers break down cooperative communication between ITS stations. However, security mechanisms for beaconing messages come with overhead that affects the overall performance. This being so, in this paper, we analyze the overhead of secure beaconing messages in terms of packet delivery ratio, delay, and normalized throughput.