| Wireless networks work using radio waves | | | | second) -- a similar frequency to mobile phones |
| instead of wires to transmit data between | | | | and microwave ovens. As you might know, |
| computers. That's the simple version. If you're | | | | though, a frequency this high means that the |
| curious to know what's going on in more detail, | | | | wavelength must be very short, which is why |
| then it's all explained in this article. | | | | wireless networking only works over a limited |
| I'm sure you know that computers transmit data | | | | area. |
| digitally, using binary: ones and zeros. This is a | | | | In addition, wireless networks make use of a |
| way of communicating that translates very well | | | | technique known as 'frequency hopping'. They use |
| to radio waves, since the computer can transmit | | | | dozens of frequencies in the range they are |
| ones and zeros as different kinds of beep. These | | | | given, and constantly switch between them. This |
| beeps are so fast that they're outside a human's | | | | makes wireless networks more immune to |
| hearing range -- radio waves that you can't hear | | | | interference from other radio signals than they |
| are, in fact, all around you all the time. | | | | would be if they only transmitted on one |
| The way it works is a lot like Morse code. You | | | | frequency. |
| probably already know that Morse code is a way | | | | The final step is when it comes to all the |
| of representing the alphabet so that it can be | | | | computers on a network sharing Internet access. |
| transmitted over radio using a dot (short beep) | | | | This is done using a special piece of wireless |
| and a dash (long dash).More importantly for this | | | | equipment called an access point. Access points |
| example, though; it is a binary system, just like a | | | | are more expensive than wireless cards for one |
| computer's ones and zeros. You might think of | | | | computer, as they contain radios that are capable |
| wireless networking, then, as being like Morse | | | | of talking to around 100 computers at the same |
| code for computers. You plug a combined radio | | | | time, and sharing out access to the Internet |
| receiver and transmitter in, and the computer is | | | | between them. Dedicated access points are only |
| able to send out its equivalent of dots and dashes | | | | really essential for larger networks, though -- if |
| (bits, in computer-speak) to get your data from | | | | you only have a few computers, it is possible to |
| one place to another. | | | | use one of them as the access point, or you |
| You might wonder how the computer could | | | | could just get a wireless router. |
| possibly transmit enough bits to send and receive | | | | That's all well and good, then, but how does |
| data at the speed it does. After all, there must be | | | | wireless equipment made by entirely different |
| a limit on how much can be sent in a second | | | | companies manage to work together when this is |
| before it just becomes useless nonsense, right? | | | | all so complicated? Well, the answer is that there |
| Well, yes, but the key to wireless networking is | | | | are standards that all wireless devices follow. |
| that it gets around this problem. | | | | These standards are technically called the 802.11 |
| First of all, wireless transmissions are sent at very | | | | standards, and are set by the IEEE (Institute of |
| high frequencies, meaning that more data can be | | | | Electrical and Electronics Engineers). It is thanks to |
| sent per second. Most wireless connections use a | | | | people sticking to their standards that wireless |
| frequency of 2.4 gigahertz (2.4 billion cycles per | | | | networking is so easy and cheap to use today. |