Traditionally, SPaT messages were broadcast via , which requires a vehicle to be within a few hundred meters of a physical roadside unit (RSU). SPaT over the network leverages existing 4G/LTE or 5G cellular infrastructure (C-V2X) and cloud platforms to deliver this data.

In the context of technology, SPaT (Signal Phase and Timing) over the network refers to the transmission of real-time traffic signal data from infrastructure to vehicles using cellular or cloud-based communication instead of just direct short-range radio. What is SPaT Over the Network?

: Provides current signal states (red, yellow, green) and the residual time remaining for each phase.

: Unlike direct radio, which is limited by line-of-sight and distance, network-based SPaT can reach vehicles much further away, allowing for earlier planning.

: It integrates traffic signal controllers with central management systems to broadcast data across entire corridors or urban networks. Key Benefits & Applications Signal Phase and Timing (SPaT) Message