CPO stands for Charge Point Operator. The CPOs main task, as included in the name, is to operate the charging infrastructure commonly via the usage of a backend. Charging stations have specific gateways to communicate with external systems. To correctly enable authentication at a charging station the infrastructure will commonly communicate with the backend of the CPO and check if there is a correct user account of an Mobility Service Provider deposited for the dedicated authentication token. If this authentication is successful the CPO will authorise the charging session and the current flow will start.