What is a MAC Address?
MAC is the abbreviation for Media Access Control. Originally designed by the Institute of Electrical and Electronics Engineers (IEEE), MAC addresses are unique 12 digit hexadecimal numbers and are used as unique as the unique hardware address of a network adapter or interface that help identify all devices on a network to enable communication between devices.
All MAC addresses are tied to the Network Interface Controller (NIC) which is where you physically connected a device to the network, i.e. via an Ethernet Cable or WiFi. The NIC is part of a larger device and is sometimes referred to as the Network Interface Card, Network Adapter or LAN Adapter.
MAC Address vs IP Address
While they are both addresses, a MAC address is a permanent address and cannot be changed. IP addresses on the other hand are dynamic and can be changed either automatically or manually. While it is true IP addresses can be made static, this change is not permanent which means IP addresses can be assigned to other devices on a network.
How Are MAC Addresses Used?
The IP address is the network location while the MAC address is the hardware address. When communicating over a network, computers use both addresses to ensure the secured, correct delivery of data packets to the intended recipient.
In Telecoms, we use MAC Addresses to identify specific hardware such as Desktop VoIP Phones, ensure that they are provisioned with the correct base configurations and finally to route calls to and from these phones.
We can access and manage the phones on a network via their IP address, but in order to ensure we are managing the correct phone, we need the MAC address.
Lost? Here’s an example from something completely different
As a simple example, you can imagine the IP address as your street address and your MAC address as your post code.
If you move one house up the road, your street (IP) address will change but your postal code (MAC) will not.
In the same way, moving to a different town BUT to the same street name and house number will keep your street (IP) address the same, your postal code (MAC) will be different.
As a result, the postal services can use both pieces of information to ensure that your post is delivered securely and correctly.