Synergizing Roadway Infrastructure Investment with Digital Infrastructure for Infrastructure-Based Connected Vehicle Applications: Review of Current Status and Future Directions

The safety, mobility, environmental, energy, and economic benefits of transportation systems, which are the focus of recent connected vehicle (CV) programs, are potentially dramatic. However, realization of these benefits largely hinges on the timely integration of digital technology into upcoming as well as existing transportation infrastructure. CVs must be enabled to broadcast and receive data to and from other CVs [vehicle-to-vehicle (V2V) communication], to and from infrastructure [vehicle-to-infrastructure (V2I) communication], and to and from other road users, such as bicyclists or pedestrians (vehicle-to-other road users communication). Further, the infrastructure and transportation agencies that manage V2I-focused applications must be able to collect, process, distribute, and archive these data quickly, reliably, and securely. This paper focuses on V2I applications and investigates current digital roadway infrastructure initiatives. It highlights the importance of including digital infrastructure investment alongside investment in more traditional transportation infrastructure to keep up with the auto industry's push toward increasing intervehicular communication. By studying current CV testbeds and smart-city initiatives, this paper identifies digital infrastructure components (i.e., communication options and computing infrastructure) being used by public agencies. It also examines public agencies' limited budgeting for digital infrastructure and finds that current expenditure is inadequate for realizing the potential benefits of V2I applications. Finally, the paper presents a set of recommendations, based on a review of current practices and future needs, designed to guide agencies responsible for transportation infrastructure. It stresses the importance of collaboration for establishing national and international platforms for the planning, deployment, and management of digital infrastructure to support connected transportation systems across political jurisdictions. (C) 2019 American Society of Civil Engineers.