An Efficient RSU Authentication Scheme based on Merkle Hash Tree for VANETs

Due to the dynamic nature of Vehicular Ad Hoc Networks (VANETs), entities in VANETs are needed to be authenticated prior to any communication between them takes place. In this paper, we present an efficient scheme for vehicles to authenticate Road Side Units (RSUs). We exploit Merkle Hash Tree (MHT) to reduce computation and communication overheads for authenticating RSUs. A detailed security analysis is carried out to demonstrate its effectiveness against message modification attack, replay attack, and message injection attack. Finally, our analysis shows that the proposed authentication scheme performs better than the ECDSA+ECDH aggregation scheme with respect to computation and communication overheads.