Build a 12-Line Python Smart Attendance System Using MAC Address Sniffing

This article demonstrates building a simple employee smart‑check‑in tool using Python in just 12 lines of code.

Step 1: Overall Idea

Leverage the fact that modern employees always carry smartphones; by capturing their MAC addresses via a USB Wi‑Fi adapter in monitor mode (range ~20‑30 m), we can determine who is present at work.

Step 2: Required Environment

Ubuntu, Python 3, a USB Wi‑Fi adapter that supports monitor mode, and the scapy and pandas libraries (installable via pip).

Step 3: Preparation

Install Python 3 and an IDE (e.g., PyCharm) on Ubuntu, then open a terminal in the Python bin directory.

Store employee information, including their phone MAC addresses, in a spreadsheet.

Enable monitor mode on the Wi‑Fi adapter and start packet sniffing; the adapter must support monitor mode.

Step 4: Python Implementation

1. Use pandas to read the spreadsheet and extract the list of MAC addresses.

2. Use scapy to sniff Wi‑Fi probe request packets, filtering with packet.haslayer(Dot11ProbeReq) to capture only client‑initiated requests.

Because modern phones randomize their MAC addresses unless they have previously connected to a Wi‑Fi network, employees must connect to the office Wi‑Fi first so their real MAC can be captured.

The script runs continuously, printing detected MAC addresses and matching them against the employee list to log attendance.

Security tip: Disable Wi‑Fi on phones when not in use to prevent unintended MAC address exposure.