basic computer part - 7

The Basics of Going Wireless

In this guide, we'll discuss the basics of connecting your computer to the internet wirelessly. It's easier to grasp what's happening if we concentrate on connecting just one computer. We'll then move on to adding more PCs. (It is assumed that you have a Broadband connection, and not a slower Dialup connection plugged straight in to your phone line.)

An ADSL Broadband Setup - Without Wireless

In the image below, you'll see a typical scenario of one PC connected to the phone line via a ADSL modem. (ADSL broadband is the one that goes down your BT phone line, if you're in the UK. If you have cable broadband then it won't.)

The image shows a red wire and a blue wire. The red wire goes from the PC to the modem. The blue wire goes from the modem to the phone line. Because it's ADSL, the blue wire first plugs into something called a Filter. The Filter then goes into the phone socket.)
If you request a web page from your computer, the signal goes down the red wire to the modem. It then travels through the blue wire, and down your phone line. The image below shows this (the yellow signal):

When the web page is found on the internet, it is sent down the blue wire, through the modem, then the red wire, and to your PC. Here's a new image:

To go wireless, the bit you get rid of is the ADSL modem (the one on the floor in the image, with the red and blue wires plugged in to it). You'll swap this with something called a Wireless Router. This can have the ADSL modem built in.

An ADSL Broadband Setup - Wireless

In the next image, the red wire is gone. It's wireless! You are requesting a web page from the internet. Notice the yellow signal. Now it doesn't need to travel down the red wire. (It still needs to travel through the blue wire, though.) It travels through the air to the modem (now a ADSL wireless router), and then down the blue wire:

When the web page is found on the internet, the signal travels through the blue wire, and then to the modem (or ADSL wireless router, as we're now calling it). After the modem, the signal travels through the air to your PC.

The great thing about wireless is that the PC doesn't need to be as close to the wireless router as it is in the image above. It can be right across the room, in another room entirely or, if you're really lucky, at the bottom of the garden! There is something else you do need, however, as well as the wireless router - a wireless adaptor. We'll see what these are in the next part.

Wireless Adaptors

In the last part, you saw a basic wireless setup. Here's the image:

If you look at the image above, you'll see that the yellow signal is travelling from the wireless router to the PC. However, the computer can't do anything with the wireless signal if it hasn't got a device to detect it. The device you need is called a Wireless Adaptor.

For PCs, Wireless Adaptors come in two varieties - ones you plug in to a USB port on your computer, and ones that you fit inside of the computer. Here's a Wireless Adaptors that plugs in to a USB port:

And here's one that fits in to the computer:

If you're nervous about opening up your computer, then go for the USB variety. But notice the antenna on the one that fits in to the computer (called a PCI card). These screw out so that you can fit bigger and more powerful antennas.

If you have a fairly modern laptop, the chances are it will come with a wireless adaptor inside of it. If it's not modern, then you can add a wireless adaptor to it. These are called PCMCIA cards. They look like this:

You probably have a slot for a card like this in your laptop. If you don't, then you can always use one of the USB adaptors.

But to go Wireless for your Internet, you'll need some form of Wireless Adaptor for your PC or laptop.

Wireless Routers

What is a Router?

A standard modem allows you to connect one computer to the internet at a time.

A router allows you to connect one or more computers at a time:

It's called a router for the simple reason that signals are being routed back and forth. The computers can be connected to the router either with a wire (called an Ethernet Cable), or without wires. We're interested in a Wireless Router. Here's a picture of one:

This model is a Linksys, one of the big players in the wireless game. Other big players are Belkin, D-Link and Netgear. Notice the two anetennas sticking out. Most wireless routers have at least one. The antennas can be unscrewed and replaced by something bigger and more powerful. Data from the internet will travel through the router and then those antennas. They are then broadcast to the Wireless Adaptor on your computer or laptop. (And any other wireless adaptor in range - whether it's yours or not! See the security section below for how to solve this)

Wireless Jargon

There's a lot of jargon associated with the wireless router you buy. In the previous section, we discussed what 802.11g was. The 802.11 is a common standard that helps devices talk to each other. The g is an improvement to the 802.11 standard. However, as of September 14th 2009, a new standard has finally been ratified, seven years after it was first put forward! The new standard is 802.11n. This newer standard offers faster and more reliable wireless signals. You have been able to get Draft N routers for some time now. But the ratification of the treaty by manufacturers means that a wireless adaptor bought from one company should work with another's routers, and vice versa.
Another bit of jargon you'll see is MIMO. This stands for Multiple-Input Multiple-Output. Which does, of course, tell you nothing! But MIMO is a technology aimed at giving you a better range for your wireless signals, and can carry more data in those signals (throughput). But you need a wireless adaptor that supports the MIMO technology, if you buy a wireless router with the words MIMO on it.
If you have a 3G connection, look out for MiFi. This is a way to share computers using a 3G connection, rather than a fixed line ADSL connection, or cable broadband. With a MiFi router you insert your SIM card into, and this connects to the internet, rather than your USB dongle. The router should then let you connect several computers to the Internet at once using wireless, ethernet, or both.

What's involved in setting up a Wireless ADSL Router?

Manufacturers like Linksys are making it easier to set up wireless routers. Look for an Installation CD, or a Quick setup option. At the very least, there should be some instructions to follow along with. If you have an ADSL broadband connection, then you'll want to buy a wireless router with a ADSL modem built in. (It will say this on the box.) The model below, for example, is Linksys WAG200G - Wireless-G ADSL Home Gateway:

The ADSL in the product name means it has an in-built ADSL modem. In other words, you won't need the modem that your Internet Service Provider gave you. If you look at the image below, you'll see a socket for Line (the white one). You plug your phone cable (called and RJ11) in to this socket. At the moment, you probably have this cable plugged in to a USB modem that you got from your internet provider:

The four yellow sockets are for ethernet cables, allowing you to connect up to four computers with a wired connection (as well as the wireless computers). But the wireless router above comes with a User Guide and Setup Wizard on CD-ROM, and it will explain all this as you're setting it up.
The first step is usually to set up your router with a direct cable connection. (Called an Ethernet or Network cable. This is usually supplied with the router). The wizard should then take you through a few steps to get you connected to the router, and on to the Internet. Before you do this, you should contact your ISP and get any router setting they may have. You'll also need your broadband username and password.
But once you have a wired connection set up, you can then set up a wireless connection. When you have your wireless connection up and running, you can then unplug the Network cable.
Look out for all those lights on your router. You'll see the following lights on the Linksys WAG200G - Wireless-G ADSL router above:
Power Turns Green when you plug the power cable in
Wireless Turns green if you get a successful wireless connection. Flashes green if data is being transferred from the wireless adaptor on your computer
Ethernet Turns green if the supplied Network cable is plugged in correctly to the router and computer. Starts flashing green when data is being transferred
DSL This is the ADSL light. It starts flashing green if it can't get a connection from your phone sockets. If it stays solid then your ADSL connection is OK
Internet Tells you whether the connection to your Internet Service Provider is OK. Will be solid green if everything is OK. This light will be red if the connection fails (if there's outage at your ISPs end, for example.)

What's involved in setting up a Wireless Cable Router?

If you don't have an ADSL connection, but have a cable broadband connection, then don't buy an ADSL wireless router. You want one that you can plug your modem in to. Look for any wireless router that DOESN'T have the words ADSL in the title.
The modem you got from your ISP will probably be connected to your computer via an ethernet cable. Unfortunately, you can't just plug this in to your shiny new wireless router and expect it to work! When you plug your Ethernet cable in to your computer, you're plugging it in to an ethernet card. Your ethernet card has a unique address called a MAC address. Cable providers connect you via the MAC address of your ethernet card. Your new router will have a different MAC address. So if you plug your ethernet cable in to this, your provider won't know where you are, and you won't get any web pages!
The good news is that there's something called MAC address spoofing. This is when the router pretends to be your ethernet card. If you get a wireless router like the Buffalo AirStation G54 High Power then the install process will take care of this for you. The process will be fairly painless. The bad news is that some routers expect you to do all this for yourself! The manual will then explain how to get the MAC address of your ethernet card, and how to enter this information in to the router. The wireless cable routers we've chosen on our recommended pages all have easy setup options for MAC address spoofing.

If something goes wrong, then you may need to gain access to what's called the Configuration pages.

What are Router Configuration Pages?

Each router will have what's called Configuration pages. You access these through a browser like Internet Explorer or Firefox. These don't come from the Internet, though, so you don't need an active broadband connection to see them. In the configuration pages, you can do things like set your broadband username and password, set up wireless security, set up online gaming, see the current status of your connection, and a whole lot more besides.
To get in to the configuration pages, you need to be connected to your router. This can either be with the Network cable, or via your wireless adaptor. Start up your browser, and enter the address for your router. These differ, but for the Linksys router it will be:

http://192.168.1.1

You will then be asked for a username and password. Routers will have a default for both of these. For the Linksys, it's admin for the username and admin for the password. (Look in your manual for the router's address and default username and password.) Click OK and you'll be in to your configuration pages.
If you can't see any configuration pages then the connection from your computer to the router is not working. So don't blame your ISP! Time to pour over those manuals!

Wireless Security

Another thing you may need to do in the config pages is to set up wireless security. If you don't have security switched on, anyone within range of your wireless router will be able to connect to it. There are two forms of security that most wireless routers use, WEP and WPA. What you are doing here is encrypting your signals with a key. With wireless security turned on, the router needs your key before it will allow any traffic through it. No key means no access.
WEP
Wired Equivalent Privacy. This is an older form of security and is not as safe as WPA. There are programmes around that hackers can download to crack WEP. Once they have WEP cracking software, they may be able to gain access to your router and get a free ride on the Internet At the very least!
The WEP key, though, will be either 64 bits or 128 bits in length. (128 bits is 26 characters, and will be mixture of the numbers 0 to 9 and the letters A to F.) If you have a Livebox from Orange, for example, then it comes with WEP security. When setting up the router for a wireless connection, you have type out all 26 characters. Get one wrong and it won't connect!
WPA
Wi-Fi Protected Access. WPA security is really an update to WEP. It uses different and stronger encryption, and so is harder to crack. It's easier for you to set up, as well, because you just need to set up a short pass phrase instead of typing out 26 letters and numbers! You should use WPA and not WEP
A lot of wireless routers don't have security turned on by default. Your configuration pages will allow you to turn it on, and there is usually a help menu which explain the various security settings.

What are wireless signals?

We have these boxes in our living room that send wireless signals to the computers. The computers then sends wireless signals back to the box. But what's being sent? Just what, exactly, is a wireless signal?

Electromagnetic Radiation

Think of the Sun. It blasts out energy. This energy is called Electromagnetic Radiation. It is electrical and magnetic. In the diagram below, the Electromagnetic wave is coming from the sun.

The energy is given different names: Gamma Rays, X-Rays, Ultraviolet, Radio waves. The length of each wave is what gives rise to the names. In the image below, we see the depiction of a wave. Notice the crests and troughs. A wave is measured from one crest to another. Gamma Rays will have a very short distance between the crests; radio waves have a longer distance.

Radio Waves

So the wireless signals in the home are radio waves. Radio waves from a wireless router are pumped out at between 2.4 and 2.5 Gigahertz (GHz). This means 2.4 to 2.5 billion waves per second. The width of the wavelength, though, will be about the same.
Waves of the same length can interfere with each other. If you have a Microwave oven, for example, the distance between the crests will be the same as the signals from your wireless router. Your wireless signals will be disrupted if they meet those of your Microwave oven, say.
Other electric devices know to clash with your wireless signals are:

• Digital phones
• A Baby's cot monitor
• Bluetooth gadgets
• Other wireless router

This is because the distance between the crests of the waves is more or less the same for all these devices, and so they clash. To solve this problem, you can change the frequency of the radio waves. On a wireless router, this is called changing the channels. What you're doing here is changing the number of waves per second. The changes you're allowed to make are from 2.4 to 2.5 GHz. You make these changes from the router's control panel (called the configuration page). So channel 1 will mean 2.41 GHz, channel 2 will mean 2.42 GHz, channel 3 will mean 2.43 GHz, and so on.
Other problems are objects getting in the way. If a signal is sent to your computer then it may get bounced off walls, windows, glass mirrors, carpeted floors, and many other objects, before it reaches your computer. At the PC end, this can mean a slow connection. The radio waves are travelling at the same rate but, due to signal bounce, it's taken longer to reach its destination. Things that can cause problems for your wireless router are:

• Glass doors, glass mirrors, glass in windows
• Shiny metallic surfaces
• Fish tanks (it's the water)
• Internal walls made of brick
• Stud partitioning in walls
• Carpets

Conclusion

So, the wireless signals bouncing around the home are radio waves. And radio waves are a form of electromagnetic energy.
It may not be such a comforting thought that we've introduced electromagnetic radiation into the home, and that's it's travelling back and forth between the computer and the wireless box! Which begs another, far more important, question: Are these radio waves a danger to your health? In the next article, we'll investigate that very worrying possibility.