What is a MAC Address, what it's used for and how to change it
🧠 What is a MAC Address
A MAC address (Media Access Control address) is a unique physical identifier assigned by the manufacturer to every network card (e.g., Wi-Fi or Ethernet). It’s permanent and used to identify the device on a local network.
Example:
00:1A:2B:3C:4D:5E
🌐 MAC vs IP Address
- MAC: fixed, physical, unique. Used to identify devices within a local network.
- IP: dynamic, can change. Used to identify devices on the internet.
Every network packet contains a source MAC and a destination MAC.
🎭 Why change your MAC address
Changing your MAC address can be useful to:
- Hide your identity
- Bypass MAC-based filters
- Imitate another device (spoofing)
🛠️ How to change it in Kali Linux
- Show network interfaces:
ifconfig
🔁 What is the lo (loopback) interface
If, listing your network interfaces, you notice a networ named ‘lo’ don’t worry!
The lo interface is an internal channel in the computer. It allows the machine to communicate with itself. Common uses:
- Local server testing
- Inter-process communication
Associated IP: 127.0.0.1 (also known as localhost).
- Disable the interface (e.g.,
lan0):
ifconfig lan0 down
- Change the MAC:
ifconfig lan0 hw ether 00:11:22:33:44:55
- Enable the interface again:
ifconfig lan0 up
- Check the change:
ifconfig
⚠️ Note: This change is temporary and will revert on reboot unless configured otherwise.