An intrusion detection system comprising: an intrusion detection controller; a plurality of sensors operatively coupled to the intrusion detection controller; each of the plurality of sensors includes: a detection mode in which the sensor applies one or more detection algorithms to sensor data generated by the corresponding sensor to detect a possible intrusion event and to report the possible intrusion event to the intrusion detection controller, wherein in the detection mode, the sensor data is not reported to the intrusion detection controller; a sensor data mode in which the sensor data is reported to the intrusion detection controller; when one of the plurality of sensors reports a possible intrusion event to the intrusion detection controller, the intrusion detection controller is configured to: instruct one or more of the plurality of sensors, other than the one of the plurality of sensors that reported the possible intrusion event, to switch from the detection mode to the sensor data mode; receive the sensor data from the one or more of the plurality of sensors that were switched to the sensor data mode; and process the received sensor data to provide a measure of confidence in the reported possible intrusion event. an intrusion detection controller; a plurality of sensors operatively coupled to the intrusion detection controller; each of the plurality of sensors includes: a detection mode in which the sensor applies one or more detection algorithms to sensor data generated by the corresponding sensor to detect a possible intrusion event and to report the possible intrusion event to the intrusion detection controller, wherein in the detection mode, the sensor data is not reported to the intrusion detection controller; a sensor data mode in which the sensor data is reported to the intrusion detection controller; a detection mode in which the sensor applies one or more detection algorithms to sensor data generated by the corresponding sensor to detect a possible intrusion event and to report the possible intrusion event to the intrusion detection controller, wherein in the detection mode, the sensor data is not reported to the intrusion detection controller; a sensor data mode in which the sensor data is reported to the intrusion detection controller; when one of the plurality of sensors reports a possible intrusion event to the intrusion detection controller, the intrusion detection controller is configured to: instruct one or more of the plurality of sensors, other than the one of the plurality of sensors that reported the possible intrusion event, to switch from the detection mode to the sensor data mode; receive the sensor data from the one or more of the plurality of sensors that were switched to the sensor data mode; and process the received sensor data to provide a measure of confidence in the reported possible intrusion event. instruct one or more of the plurality of sensors, other than the one of the plurality of sensors that reported the possible intrusion event, to switch from the detection mode to the sensor data mode; receive the sensor data from the one or more of the plurality of sensors that were switched to the sensor data mode; and process the received sensor data to provide a measure of confidence in the reported possible intrusion event.