Formally Validated of Novel Tolling Service With the ITS-G5

The arrival of the connected and/or autonomous cars offers countless opportunities for both the user and service provider. In this paper, we present a novel solution for tolling transaction using ITS-G5 technology. Specifically, it investigates how to secure tolling transactions performed with the cooperative intelligent transportation system (C-ITS) equipment and the tolling server as a trusted party. In this novel solution, we consider ITS components using the ITS-G5 technology with features specified by the European Telecommunication Standardization Institute (ETSI): RoadSide Unit (RSU), On-Board Unit (OBU), and the standardized architecture of the Electronic Fee Collection by the International Organization for Standardization (ISO). To perform the tolling transaction, a point-to-point protocol must be established between the RSU of the infrastructure and the OBU embedded in the vehicle. Therefore, we design an efficient architecture that ensures the security of exchanges is guaranteed by the security back office of the tolling server as a trusted party. From the application to the service and until its usage, some security requirements are verified: mutual authentication between all entities involved in the transaction, confidentiality, integrity, and non-repudiation of all exchanged information. The certificate usage combined with the signature process certifies the mutual authentication between each entity: the OBU with the RSU, the payer with the service provider and the RSU with the tolling server. The encryption of the messages and the verification of the signatures ensure the confidentiality, the integrity and the non-repudiation of all exchanged information. The safety and efficiency of the proposed method are validated through its formal verification using the security protocols verifier tool AVISPA (Automated Validation of Internet Security Protocols and Applications). Furthermore, the proposed architecture requires reasonable resources which will be suitable for vehicle-to-infrastructure (V2I) communications.