A Rapid Certification Protocol from Bilinear Pairings for Vehicular Ad Hoc Networks

The research of message certification in Vehicular Ad Hoc Networks (VANETs) has been focused on two aspects. One is the On Board Unit (OBU) certificates with Road Side Unit (RSU) one by one, and another is RSU goes to the batch certification after it collects a certain number of vehicle´s messages. However, when the number of messages received by RSU is accumulated to certain extent, it is difficult for RSU to certificate every received message in the above schemes. In this paper, we propose a Rapid Certification Scheme (RCS) using certificateless public key cryptography, where a Leader On Board Unit (L-OBU) is elected from a motorcade and the L-OBU can represent this motorcade to certificate with RSU. Through this way, the transmission overhead and computing overhead of RSU can be greatly reduced. At the same time, the proposed scheme can achieve privacy preservation and retrieve the real identity if necessary. Through the simulation, the proposed scheme can certificate a larger number of vehicles than other schemes in the same period. In addition, the RSU´s valid service ratio reaches over 85%, so the proposed scheme is feasible.