what is MAC address

What is a MAC address in Networking

What is a MAC address:

Often you have heard the MAC address and wonder what is the term MAC term about. When you access the internet, you are served with pages based on your IP address. Your computer sends its IP address but as it turns out, IP addresses only get you as far as the modem you have in your office or house. And these days most of us has several devices at home or office connected via our routers including smartphones, gaming consoles, laptops, tablets, computers, IP boxes, Chromecast etc. And they’re all connected nearly at the same time, constantly communicating with the Internet world via your Modem. How does the system know what info is to be sent to which device on the local network? Well, each connected device on your local network has something called a MAC address. MAC stands for Media Access Control and it identifies which device is which on your local network.


So here’s how they work: When data arrives at your home from the worldwide Internet, your router needs to decide which device to send that data to. It does this by keeping track of the MAC addresses of all the devices connected to it. Then assigning what is called a private IP address usually starting with 192.168 to every device.  This is also why you usually enter or input those numbers to access your router’s control panel through your browser.  This is very different from a public IP which is what the rest of the Internet sees. The Modem IP is basically your unique IP address for your entire network.  This is what comes up when you type what’s my IP address into Google.  Your router keeps track of outbound request such as when you click on a link. So when the data you want arrives at your router, it attaches the correct private IP address to the data packets ensuring that they go to your computer or device since all those private IPAs correspond to the correct MAC address.  This might understandably seem a little redundant since if your computer now has both a private IP and a MAC address, that can both individually identified. But in reality, you need both since all the public and private IPAs stays the same throughout this process, the MAC addresses on the data packets, are constantly being changed. They only tell the date of where to go for its next hop.  when your data go to the next device, the MAC address is changed in order to tell it where to go next. Since your data might go through numerous servers and routers before it finally gets to your device, MAC address information is crucial even though you have a private IP. The other upside of MAC addresses is that normally they always stays the same with many devices having their MAC addresses hardcoded into the firmware at the factory making it easy to spot a malfunctioning device on the network or if you’re trying to troubleshoot.  You can also protect your network by adding hard-coded MAC based devices into the network. You can also use the routers to restrict certain MAC addresses to restrict access to known devices. For more information about Network and Network cabling, please get in touch with us.