Buses communicate with traffic signals, allowing adjustments in the traffic signal timing to keep buses on schedule. Application of TSP does not require a dedicated lane for the bus. 

TSP applications can be active or passive

• Active TSP changes the traffic signal timing based on the buses’ conditions including the number of people on the bus or if the bus is running late
• Passive TSP changes the traffic signal timing when a bus arrives at a signal, regardless of the current conditions