Source: upload.wikimedia.org

Computer networks are amazing things. They are a complex matrix of channels and links forming virtual communication networks. These networks give way to unimaginable and almost instant virtual applications. Either through games, streaming video, chat, telephone or internet, the link between the physical world and the virtual world seems to sometimes magic.

But how the computers bridge the gap between the two worlds. Where on the network of the physical domain is virtual.

How to communicate the computers?

Each computer or device needs to go talk to another computer on the network is a network (NIC) interface card. NIC most is to be integrated as a wireless connection, or are installed on the computer. When a network adapter is made, the manufacturer encodes a unique hardware address in it permanently. This address encoded permanent equipment is stored in the read-only part of the memory card and is known as the MAC (Media Access Control) address.

A MAC address is a 48-bit physical address which is used to physically identify the computer on the network. This 48-bit address is usually displayed in hexadecimal (base 16) as a 12-digit number.

This is an example of a MAC:

MM: MM: MM: HH: HH: HH

A true MAC would look like this:

d 00: 1 (b): 21: 44: EB: 8

The first half of the MAC, the first 6 digits (24-bit), the address represents the portion of the vendor or manufacturer of the network adapter. Each manufacturer of the network adapter is assigned a unique identifier by the IEEE for all of their network adapters. The last 24 bits (6 digits) are a unique identifier that represents the adapter itself. Each manufacturer will be their unique network interface card number. No two MAC addresses are similar.

This 48-bit MAC address is the physical computer device on the network. It is the bridge between the physical world and the virtual world of computer science. It is the link between the physical hardware and the virtual operating system.

All computers communicate using the MAC address. Most people believe that computers use IP addresses to communicate. And they do, but under the IP address is the MAC address and this is where the real communication takes place.

So the next time that you need to find a computer on your network don't forget to find the MAC address. Once find you the MAC address, you can find the computer itself.