Any computer upgrade for small to medium-sized businesses is going to involve one burning issue these days: Should it include a wireless network?

The most popular type of wireless network is called Wi-Fi (for wireless fidelity), or the 802.11b standard (in techspeak), and it allows workers within a company to roam the building while remaining connected.

This is seen as so important that makers of laptops are starting to put Wi-Fi in their notebook computers as a matter of course. More important, wireless networks mean fewer cables to install and therefore fewer expenses to worry about when changing the office staff and furniture about. In short, wireless nets are an intelligent, cost-effective purchase.

The market is buzzing with new Wi-Fi systems. But so are terrifying accounts in the tech press.

Not a day seems to pass without a report that bands of digital devils are playing a game they call "war driving." It grew out of an earlier activity called war dialing, popularized in the 1983 movie War Games, in which software was used to dial many phone numbers automatically, looking for lines answered by modems.

The modern version involves driving around a city with a laptop computer equipped with a Wi-Fi network card and an antenna looking for unsecured networks. Wardrivers always report an astonishing number of networks that are not protected, in some cases allowing unauthorized users to surf using other peoples' Internet connections or gain access to corporate networks. An offshoot of wardriving is warchalking, a technique picked up from Depression-era hoboes, of marking buildings with chalk symbols that signify to other hackers the presence of insecure networks.

It's enough to scare any venture off the idea entirely.

But there are ways around the problems.

First, you have to take a pinch of salt with the wardrivers' number of insecure networks. These kids get their jollies making fun of grownups who should know better about security, and so higher numbers mean bigger thrills for wardrivers (though they insist they're not mobile hackers; they don't even try to log into the networks they find).

What they are not telling you, however, is how many of these unprotected nets have security beyond simple access. Wardrivers may, for instance, find an open network, but be confronted with a log-in screen before they are able to rummage about in your e-mail.

Remember also that Wi-Fi networks are effective for relatively short distances only; a hacker would usually have to get within 100 metres of an access point or antenna, depending on the kind of walls the signals have to travel through and competing radio noises. (Canadian winters provide a good level of security in this respect.)

Before installing a network, you have to decide how secure you want it to be. Most Wi-Fi networks feature a system called wireless encryption protocol (WEP), which is referred to as weak encryption, meaning it will be secure against casual hacking (as long as the person setting up the network remembers to turn it on, a common oversight by amateurs). A determined hacker can crack that WEP-enabled system within 15 minutes with the proper software tools.

But for some small enterprises with few enemies or disgruntled former employees, WEP may just be enough, especially if the individual computers on the network have their file-sharing option turned off. Computers configured this way do not show up on the network, and so are much more difficult for hackers to break into.

Networks exist to share resources and data, and turning off file-sharing tends to defeat that purpose. Still, it's possible -- depending on the enterprise -- to put certain kinds of data on shared drives, leaving the individual computers protected.

If WEP offers a measure of security, the trade-off is in inconvenience. Every user must be educated in how it works, their computers must be reconfigured to connect to the network, and the encryption code should be changed frequently, which gets progressively more difficult as the enterprise gets larger.

Moreover, every authorized user must be given the encryption key and, as a result, there will be a lot of people out there carrying around the keys to your kingdom.

The Wireless Fidelity Alliance, an industry trade group, will soon announce the details of a new security standard called Wi-Fi Protective Access (WPA), a more complex security coding system. Products using this system are expected to be available after February, so it may make sense for businesses concerned about both security and budgets to wait a few months before buying a wireless network.

Before that, one can use individual programs' built-in security systems. Many word-processing programs allow users to create password-protected documents. A company's mail can be put on a server featuring Web access, meaning hackers would have to come up with a password more difficult to crack than a WEP code before getting at your e-mail.

At the next level up, users can be required to authenticate themselves using secure sockets layer (SSL) encryption, the leading encryption system on the Internet. It sits on the company server and requires users to sign on with their identification codes before they can get into the network. This way a company can log whose account was used to gain access should any security issue arise.

Even more secure are firewall-protected networks, but Wi-Fi connections would have to be forbidden behind them. Still, a wireless network could be put in front of a firewall; users outside will have to connect via an SSL password-protected log-in, while users on the inside could enjoy the full benefits of the network.

Symantec Corp. and other companies make products that can be either bought off the shelf for small enterprises or installed as a service for larger operations. All versions also come with virus protection, intruder alerting and other features.

When a decent firewall is put in place, the only way to get access to the corporate network is through a virtual private network (VPN), which is a wire-based system, and shouldn't be run over Wi-Fi.

The costs are not prohibitive; all a wireless network needs to make the company run more effectively is just a bit of thought.

And forget those war drivers. They exist only to enjoy your feelings of insecurity.

For more tech news and Jack Kapica's regular column, see http://www.globetechnology.com.

E-mail Jack Kapica at jkapica@globeandmail.ca

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