Roadside-vehicle cooperative illumination system

A roadside-vehicle cooperative illumination system comprising an in-vehicle apparatus mounted in a vehicle and responsible for controlling a headlight of the vehicle and a roadside apparatus positioned along a roadside and responsible for controlling a road illumination lamp, the headlight and the road illumination lamp being controlled cooperatively through communications between the in-vehicle apparatus and the roadside apparatus, wherein

• the in-vehicle apparatus comprises:
• a communication unit that communicates with the roadside apparatus;
• a detector that detects information pertaining to operation of the headlight of the vehicle;
• and
• an arbiter that transmits a request to the roadside apparatus for altering at least one of an illuminance and an illumination range of the road illumination lamp on the basis of the information pertaining to operation of the headlight of the vehicle detected by the detector;
• and
• the roadside apparatus comprises:
• a communication unit that communicates with the in-vehicle apparatus;
• an arbiter that determines whether or not to accept the request from the in-vehicle apparatus side arbiter, and determines at least one of the illuminance and the illumination range of the road illumination lamp on the basis of the determination of whether or not to accept the request from the in-vehicle apparatus side arbiter;
• and
• a controller that controls the road illumination lamp according to the at least one of the illuminance and the illumination range of the road illumination lamp determined by the roadside apparatus side arbiter.