TA is a trusted third party that is responsible for the gratification and distribution of private and public keys for OBUs and RSUs. The public key of each entity in the system is certified by a trusted party, so that the corresponding certificate can be subject to public scrutiny. This trusted part is also responsible for the management of certificates. In addition, the system is initialized and the system settings are generated. Before executing the key agreement, OBUs and RSUs must legally be registered in THE TA. TA assigns the corresponding RSUs and OBUS authentication settings. TA can track the actual identification of the vehicle when it is necessary to achieve traceability . The necessary preparation work is carried out during the initialization phase, which can usually be categorized in user registration and key information allocation. It is desirable that each vehicle registers first at TA. Subsequently, TA assigns the secret information to the corresponding vehicle. In addition, TA stores drivers` personal data, such as license plate, contact information and address. Leave the generator of a group of cyclic additives and be the unique identifier for the vehicle. In addition, TA provides safe hash functions, which are defined as a whole non-negative number, which is smaller than the large prime number.
Therefore, TA generates the secret key for each vehicle assigned to the vehicle after the user`s registration. Note that the secret keys of all registered vehicles are stored securely in the TA database. At the same time, TA selects an entire random whole as a private RSU key. Leave the cyclic additive group generated by the order. Therefore, the public key of the RSU according to him worth ing, that the public key of the RSU, the generator, the function of haue , and will be published on all devices while the private key is kept secret throughout the process. TA assigns each legitimate vehicle unique n-dimensional vectors TIDi, ai and bi. TIDi refers to the true identity of the vehicle, ai is the common secret between the Vi and TA vehicle, and bi is the common secret between the Vi vehicle and the RSU.