This design uses RFID tag technology to enable low-cost, battery-free, and easy-to-install home security systems.

The authors propose the use of RFID technology and an Arduino board for the same. Every product will have an RFID (Radio-Frequency IDentification) tag (instead of barcodes being used conventionally).

After you've assembled the rather complex contraption, you affix color-coded RFID tags to your gadgets, before registering them with the Arduino-based host.