This International Standard provides the requirements for an electronic registration identification (ERI) using symmetric encryption techniques that are based on an identifier assigned to a vehicle (e.g. for recognition by national authorities), suitable to be used for - electronic identification of local and foreign vehicles by national authorities, - vehicle manufacturing, in-life maintenance and end-of-life identification (vehicle life-cycle management), - adaptation of vehicle data, e.g. in case of international re-sales, - safety related purposes, - crime reduction, - commercial services, and - adhering to privacy and data protection regulations.This part of ISO 24534 specifies the interfaces for a secure exchange of data between the electronic registration tag (ERT), which is the onboard device containing the ERI data, and the ERI reader or ERI writer in or outside the vehicle using symmetric encryption techniques. Symmetric encryption techniques are based on secret keys shared by a particular community of users, i.e. in closed user groups in which it is trusted that keys are not revealed to outsiders. It includes - the interface between an ERT and an onboard ERI reader or writer, - the interface between the onboard ERI equipment and (roadside) reading and writing equipment, and- security issues related to the communication with the ERT.NOTE The vehicle identifiers and possible related vehicle information (as typically contained in a vehicle registration certificate) are defined in ISO 24534-3.