Most of us have Internet routers in our homes, offices or schools. You know that the router is necessary to get online, but what exactly does it do? How does that small plastic box get information from your computer to somebody else's? To understand how a router works, you first need to know about Internet packets.
What Is a Packet?
A packet is simply a tiny bundle of digital information. Every email you send, every website you visit and every video you watch online are all broken down into packets. Each packet contains information about where it comes from, where it is going to and how many other packets it is being sent with. For example, if an email is divided into ten packets, each packet lets the receiver know that there were nine more packets joining it.
From Binary to Electricity
When you write an email, your computer has to convert it into a format that other computers will understand. Computers transmit information in binary code, which is a series of ones and zeros. All packets are first converted into binary code and then into electrical signals. These signals are sent from your computer along a cable (in the case of an Ethernet connection) or through the air as radio waves (if you are using a wireless connection).
The Router Delivery System
Your router receives the packets as electrical signals and sends them to your Internet service provider. Before the signals can get to their intended recipient, they first have to travel through many more routers. Think of a router network like the postal service. One postal worker picks up a letter from your house and delivers it to the post office. A mail sorter figures out where all the letters need to go. If a letter is traveling a long distance, it may need to be carried by multiple vehicles (trucks or planes) and hit several interim sites before it reaches the recipient's home. In similar fashion, but using a series of routers instead of mailmen and vehicles, an electronic signal is ferried along its way from origin to destination.
After a signal reaches the router that the recipient's computer is networked with, the conversion process begins again. The electrical signals are turned back into packets of binary code. Your computer reads the binary code and converts it into information that a person can understand, such as text, pictures or music. This entire process--from when you click "Send" to when they get their email--takes place in the blink of an eye.
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