The system works by analyzing radar and satellite tracking data from Airport Surface Detection Equipment, Model X (ASDE-X) systems. ASDE-X systems use surface radar, multilateration, and in some cases ADS-B (Automatic Dependent Surveillance-Broadcast). The ASDE-X data includes location information for aircraft and vehicles. The RWSL system uses complex algorithms to calculate future paths and predict potential conflicts. The system automatically illuminates lines of bright red lights in the pavement of select runways when a potential conflict is likely to occur between two aircraft or vehicles. The RWSL arrays on taxiways light up any time an aircraft is landing or about to takeoff. The lights extinguish as soon as it is safe to move forward.