How do routers work?

Answer 1

Keeping the Messages Moving
When you send e-mail to a friend on the other side of the country, how does the message know to end up on your friend's computer, rather than on one of the millions of other computers in the world? Much of the work to get a message from one computer to another is done by routers, because they're the crucial devices that let messages flow between networks, rather than within networks.

Let's look at what a very simple router might do. Imagine a small company that makes animated 3-D graphics for local television stations. There are 10 employees of the company, each with a computer. Four of the employees are animators, while the rest are in sales, accounting and management. The animators will need to send lots of very large files back and forth to one another as they work on projects. To do this, they'll use a network.

When one animator sends a file to another, the very large file will use up most of the network's capacity, making the network run very slowly for other users. One of the reasons that a single intensive user can affect the entire network stems from the way that Ethernet works. Each information packet sent from a computer is seen by all the other computers on the local network. Each computer then examines the packet and decides whether it was meant for its address. This keeps the basic plan of the network simple, but has performance consequences as the size of the network or level of network activity increases. To keep the animators' work from interfering with that of the folks in the front office, the company sets up two separate networks, one for the animators and one for the rest of the company. A router links the two networks and connects both networks to the Internet.

More Info :
http://computer.howstuffworks.com/router1.htm

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Answer 2

Simple answer;

It kinda works the way the post does. You send a letter and it goes to the postoffice, if the person you are sending it to lives in the same postal area, they send it straight to their mailbox. If not, they send it to other post offices based on zipcode, in a chain until one *does* know that address.

Routers contain a table of routes, that is, a list of ways of getting across the internet. By default, your home router probably only contains two entries in the table;

If the IP address I am looking for is another one on my network, for instance it's my printer, just go straight there.

Otherwise, go to my ISP, and ask *them* what to do from there, and they'll send it to other ISPs, based on bits of the IP address. Of course you can have direct routes to private networks (your New York office to your Seattle one) and that's kinda just like using a courier.

That's how routers work.

Answer 3

The Internet is one of the 20th century's greatest communications developments. It allows people around the world to send e-mail to one another in a matter of seconds, and it lets you read, among other things. We're all used to seeing the various parts of the Internet that come into our homes and offices -- the Web pages, e-mail messages and downloaded files that make the Internet a dynamic and valuable medium. But none of these parts would ever make it to your computer without a piece of the Internet that you've probably never seen. In fact, most people have never stood "face to machine" with the technology most responsible for allowing the Internet to exist at all: the router.

Routers are specialized computers that send your messages and those of every other Internet user speeding to their destinations along thousands of pathways. In this article, we'll look at how these behind-the-scenes machines make the Internet work.

So easy, just a few touch of your fingertips on keyboard for research will resolve your question ^_^

Answer 4

That's a great question, short and to the point, but the answer is complicated and difficult to deal with here.

To learn more about routers, go to How Stuff Works or Wikipedia at:

Answer 5

As the name implies, they route packets from the internal network to the external network and vice versa.

Routers are a central point, a device that sends data packets to and from the network.

Answer 6

it is good answer , but i think routers are the responsibility of controlling the Internet speed

Answer 7

I can't really explain everything in this page but following is the link which can answer your question.