DATA NETWORKING, e-mail sharing and surfing the Web, all from any computer in the office and without cables? The time and price are right. For small offices and home offices, wireless local area networking (WLAN) based on Wi-Fi (802.11 format) is an easy-to-set-up, affordable, increasingly popular alternative to wired LAN.

WLAN uses radio waves to transmit digital data short distances. It enables the sharing of a single broadband connection that allows everyone in the office access to the Internet simultaneously and provides the ability to share files, printers, scanners, back-up drives and other devices as well, without a wired infrastructure.

Wireless networking has been available since the late 1980s. Until 2001, however, there were no standards, making interconnection of devices by various manufacturers impossible.

Now an industry trade association, the Wi-Fi Alliance, has approved uniform (802.11) standards that support interoperability of connected devices. The standards are 802.11b, 802.11a and 802.11g.

Though theoretical ranges of 802.11b and 802.11g devices are commonly expressed to be 1,000 ft., walls and other solid items in a room reduce the signal travel distance. Practical ranges are about 100 to 150 ft.

The 802.11a format, which does not go through walls and floors as well as the other two standards, extends out only 25 to 75 ft. After those distances, the farther a device is from the transmitter, the weaker the signal and the slower the transfer rate.

Setting up a basic wireless network for sharing a broadband or DSL network requires two types of equipment: a wireless broadband router, which has the access point built in and acts as a transfer station for signals from your computers and other wireless devices and from the Internet, and one network interface card equipped with a radio transceiver for each computer you want on the network. (If you’re buying a new desktop or notebook, you can have a network card factory installed.)

To maximize results, place the router in an open area in the office, as high up as feasible, in a direct line of sight to as many computers as possible.

If you need to expand coverage within your office, you can add multiple stand-alone access points at the edges of the original range that, set to repeating mode, amplify the signals and send them farther out spherically.

You could also install a more powerful router, for example, one with 100 milliwatts of output power rather than 33 milliwatts (which is an entry level product). You might add a powerful antenna to the router or use a power booster that can boost a 33 milliwatt signal to 250 milliwatts.

Many routers include built-in print servers that allow any printer connected to the router to print on any networked computer. Alternatively, you can attach a wireless print server to the printer that will take a message to print from any networked computer.

Wireless networks, left unsecured, could be easy prey for hackers. Make sure your firewall software is activated as the first line of defense and use anti-virus software on every computer. Look for products that contain the new WPA (Wi-Fi Protected Access) standard, configured around the still-in-development 802.11i security standard. The WPA encryption key changes often for continuing security.

Also, change factory-set encryption settings on network devices (such as the SSID — service set identifier — the name of your wireless network) and activate the MAC (media access control) address filtering, if available.

Improvements in components and high volume of production have brought prices of wireless devices down dramatically, to about a third of what they were just three years ago. (A basic system set-up can run $150 to $200.) And, as a bonus, you can use your wireless-enabled notebook at any public “hotspot” (airport, mall, hotel, café, university quad or other space that provides high-speed Internet connection and wireless connectivity, free or for a nominal fee). Most hotspots currently use the 802.11b standard, but 802.11g is expected to predominate shortly.

William and Patti Feldman provide Web content for companies and write for magazines, trade associations, building product manufacturers and other companies on a broad range of topics. They can be reached at wfeldman@att.net.