An Efficient (t, n) Threshold Authentication Scheme for Vehicular Ad Hoc Networks

Vehicular Ad Hoc Network(VANET) is a hot topic, how to design an efficient authentication scheme is the core problem in this field. With the considerable progress in computing capability and side-channel attack capability, some seemingly safe third parties have also become less safe. Our paper focuses on weakening the use of trusted authority(TA) and improving the fault tolerance of authentication schemes. At first, all private keys are generated by users. Next, the ephemeral Diffie-Hellman key exchange scheme is used to construct a PID authentication. Moreover, we build a partial key delivery method without a secure channel. In the batch message authentication part, we use the Shamir secret share method to build a (t, n) threshold signature scheme that guarantees batch signatures cannot be tampered with fewer than t people involved. Finally, we make a comparison of time cost and communication cost with the other four schemes. Our scheme has a remarkable advantage over other schemes by comparing experimental data.