The entire device consists of iButton Chuck, alphanumeric LCD display, control and communication module. The system can be powered from the USB bus or external sources. On the front cover of the device is the LCD screen, iButton buffer and signal LEDs. The control module includes a microcontroller, RTC (real time clock), the external memory, and executive level that provides physical access control. The user logs on the system by touching the iButton key, then the system controls module monitors whether the key is logged in the database (in the external memory or PC).
The original purpose of the system is to provide physical access to a protected area . iButton electronic keys are durable and resistant, they are cheaper than most RFID cards. iButton is comparable to much more expensive biometric systems.