In one embodiment, a supervisory service receives a registration message broadcast by a first vehicle and captured by a RSU in the network of RSUs. The supervisory service registers the first vehicle by validating a signature of the registration message without registering a media access control (MAC) address of the first vehicle and without causing to send a registration response to the first vehicle. The supervisory service receives a message broadcast by a second vehicle addressed to the first vehicle and captured by at least one RSU in the network of RSUs. The supervisory service selects one or more RSUs in the network of RSUs to re-broadcast the message. The supervisory service controls the one or more RSUs to re-broadcast the message.