Fig.1: this computer has accessed a variety of wireless networks in the past - hence the list. Notice the little red "X" through the icon. That means it can't find them at the moment.

In our introduction to practical WiFi last month we looked at the differences between the various wireless networking standards. Fortunately, setting up the two most popular, 802.11b and 802.11g, is pretty much identical. All you have to do is decide which type of wireless network you require.

However, there is more to 802.11g than simply faster speed. They also (usually!) offer higher performance than 802.11b (see separate panel, "It’s more than just speed").

To briefly recap, there are two types of basic wireless networking: ad-hoc and infrastructure.

For either type, for each computer to be connected to the wireless network you’ll need a Wireless Network Adaptor (they’re also known by a variety of other names, such as a Wireless NIC, or network interface card; Wireless Dongle, Wireless Card and so on).

Many computers these days, especially newer laptops, come with the adaptor built in. But even many motherboards today offer integrated 802.11g facilities.

If all you want to do is share files between computers, perhaps print a document on one computer via a printer attached to another, that’s all the hardware you will need. It’s called an ad-hoc network. It’s also sometimes called a peer-to-peer or computer-to-computer network.

Fig.2: we want this to be an ad hoc (ie, computer-to-computer) network. Here's where we select this option.

If you want to use your wireless network for more advanced tasks – to connect to the internet or to another network, for example – an infrastructure network may be required. And for that, you need another piece of hardware called an access point (AP). (Again as we said last month, access points can be entirely software – see separate panel, "SoftAPs").

And just to clarify one thing: just now (and last month) we said that if you want to connect to the internet, you may need an infrastructure network. We also said last month that Windows XP takes much of the hard work out of setting up any form of network (including wireless).

Well, Windows XP goes even further than simplifying connection. It also allows you, via the "Sharing a Connection" option, to connect to the internet using an ad-hoc network. The steps are explained elsewhere but it is quite simple.