Networking allows computers to share resources like files, printers and internet connections, but all that wiring can be a pain. Worse, it may not be practical to hook them up with cables. Which is where wireless technologies come in - offering powerful cable-free networks in schools and homes with full access without a wire in sight.

Who should use it?

Wireless networking was developed for notebook hot-deskers in large offices, who wanted to stay connected to the corporate network. But a fall in prices means wireless networking is available to all.

Equip a classroom or hall with a wireless network and tens or even hundreds of people will be able to connect and share resources. It’s not just for portables either - wireless access allows you to use desktop PCs or Macs without being close to a wired network point.

Wireless is equally good in the home too, where a single broadband internet connection could be shared in every room and even out in the garden without a wire in sight. It’s also ideal for situations where cabling is undesirable or downright impossible, a godsend whether you’re in a listed building or don’t like the idea of snaking cables up the landing.

Wireless standards There are many different wireless technologies, designed for different jobs. For example, Bluetooth is a short-range standard designed to replace the wire between, say, a mobile phone and a headset. The most appropriate technology for wireless networking though is technically known as IEEE-802.11. It’s a wireless version of the ethernet networking standard and is available in several flavours.

The most widespread version is called 802.11b and equipment that will work together has a “Wifi” tag. This version runs at speeds up to 11Mbits and has a maximum outdoor range of 100 metres, although it may be nearer 10 metres indoors depending on wall thickness.

A faster version is 802.11a, which runs at up to 54Mbits, but employs a different radio frequency, making it incompatible with existing Wifi products. And currently emerging is 802.11g, which matches the speed of 802.11a, but uses the same frequencies as Wifi. Some devices now offer Wifi and 802.11g.

What you need Wifi speed and coverage is more than adequate for most people, so the bare minimum is to make sure it’s in the required computers, portable or otherwise. Many new portables (like the new tablet PCs) have Wifi built in, but if not, it can be added with an adaptor, available in PC Card or Compact Flash formats for portables, internal PCI cards for desktops or as USB adaptors which can be plugged into almost any machine. Prices start at around pound;60 per adaptor, although packs of two USB models can be often had for less than pound;100 - great for wirelessly linking two machines together.

While Wifi can be used for linking two computers directly, the real flexibility comes with full network access. In this case, a transceiver - a wireless access point - is linked to the existing network hub with an ethernet cable (see box below).

All wireless computers then connect to the network via the access point.

For the best range, the access point should be mounted high up in a room, but extra units can be fitted for greater coverage. Wireless access points cost around pound;120.

Security Wireless networks will normally penetrate exterior walls by a few metres, so if you don’t want just anyone accessing your facilities, ensure you have activated security. Wifi has built-in security, which involves entering a key word or number into the access point then giving this out to all users.

And finally...

One of the most exciting things about wireless access is that it’s not limited to private homes, schools or offices - many hotels, airport lounges, train stations and even coffee shops now offer high-speed internet access to anyone with a Wifi-equipped portable. Some ask you to pay, while others offer it as a free incentive for you to pay a visit.

BT is leading the way with its Openzone programme, which currently has 78 public “hotspots” in place (see www.bt.comopenzone for locations), and coffee shops like Starbucks have followed suit. Wifi is also an international standard, so you can take your portable abroad and use public hotspots there too. In fact, as Wifi hotspots spring up in more places, the question is: “Who needs 3G phones?”

Gordon Laing is a freelance writer, broadcaster and former editor of Personal Computer World magazine

BUILDING A PERFECT NETWORK AT HOME

An increasing number of homes have two or more computers and it’s very simple for them to share the benefits of broadband. Better still, a wireless access point makes broadband use portable.

The key to sharing broadband is a device called a router. Most routers for the home include a hub with four network plugs; you can connect any combination of PCs, Macs, notebooks or even suitably equipped games consoles like the Xbox.

Broadband routers are available for cable or ADSL connections and those designed for the latter can even have built-in modems, which is great news for new ADSL self-install customers who would have to buy a pound;70 modem anyway.

Going for a broadband router makes more sense, especially when models like D-Link’s DSL504 or Netgear’s DG814 include ADSL modems and four network ports from around pound;120. All you need is an ethernet port on your computer then you connect it to the router.

The next step is to connect a wireless access point to the router, such as D-Link’s DWL-1000AP or Netgear’s ME102 (around pound;120). This enables broadband access with any Wifi-equipped computer - handy if you don’t want to run a cable to the back room or just fancy browsing on a laptop while watching the TV.

The bottom line is you’ve paid for an always-on internet connection, so make the most of it. Once you’ve shared broadband between the family, the monthly subscription doesn’t seem so much anymore.