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. <EOS>