MAC & IP addresses

MAC address

A Media Access Control (MAC) address is a 48-bit address that is used for communication between two hosts in an Ethernet environment. It is a hardware address, which means that it is stored in the firmware of the network card.

 

A MAC address is supposed to be globaly unique. Each network card vendor gets its share of addresses (represented by the first 24 bits).

 

The address is written in the form of 12 hexadecimal digits. For example, consider the following MAC address:

 

D8-D3-85-EB-12-E3

 

Every hexadecimal character represents 4 bits, so the first six hexadecimal characters represent the vendor (in this case, Hewlett Packard).

How to find out your own MAC address?

If you are using Windows, enter the Command Prompt (Start – Programs – Accessories – Command Prompt). Type the ipconfig/all command and you should see a field called Physical address under the Ethernet adapter settings:

If you are using Linux, type the ifconfig command. You should see your MAC address referred to as HWaddress.