V2I (Vehicle-to-Infrastructure) is V2X communication between vehicles and road infrastructure such as roadside units, traffic signals and traffic-management systems.
What counts as infrastructure?
Examples can include roadside units, traffic signals, intersection controllers, tolling equipment and traffic-management systems. The exact architecture depends on the deployment.
What can V2I be used for?
Possible applications include signal-phase information, red-light or intersection warnings, road-work alerts, priority for emergency or transit vehicles, and traffic-flow coordination.
Does V2I have to be direct?
No. Some V2I functions use direct local communication. Others can be delivered through a cellular network and backend. This is one reason modern V2X discussions increasingly distinguish the application type from the underlying communication path.
Related terms
Sources
Automotive terminology evolves quickly. We separate established standards from manufacturer-specific names and update pages as technologies move into production.