When wireless local-area networks (WLANs) first became news, the discussions were mostly about big organizations and big spaces, like airport concourses and cavernous distribution centers and warehouses.

Today, WLAN technology has matured, security has been addressed, the costs have come down, and WLANs are not just for big companies or spaces anymore.

The only question that remains for most companies is how to go about implementing a wireless solution.

1. WLAN components

A WLAN consists of two main components: an access point, which acts as the receiver of the wireless signal and transmits it to the internal cable, and a network interface card. The access point is a bridge that moves packets from the wired infrastructure and transmits and receives them over the air using standards based on IEEE 802.11 technologies.

Access points can extend to distances of approximately 350 feet. When using multiple access points coupled with a feature called "seamless roaming," WLAN technologies have the ability to cover a building or floor, enabling users with laptops or handhelds to roam freely across the wireless network without any interruption of service.

The wireless network interface card (NIC), also called a client adapter or wireless adapter card, is very similar to a modem. It has drivers, tools, and utilities to set specific parameters, and it sends and receives information over the air. These cards are easily installed and are beginning to be embedded into laptops and other mobile devices, eliminating the need to install or configure them separately.

A simple WLAN deployment, such as the type that can be used in a home office or very small office, requires an access point along with a broadband Internet connection such as DSL or cable. With an access point added to the home network, users can roam freely, working in any room or even outdoors.

2. How WLANs are deployed

WLANs are usually deployed in either single-cell or multi-cell configurations.

• Single-cell deployment: This is used for small office or home office environments where only a few devices (25 or fewer) are used across distances of up to 350 feet. In these deployments, DSL or cable modems provide high-speed Internet connections.

• Multi-cell deployment: Multi-cell deployments are most commonly used for in-building WLAN coverage, because they provide edge-to-edge wireless connectivity in areas larger than 350 feet.

3. Keeping it simple

There are several features to look for in a WLAN to help simplify deployment. These include Web-based management and frequency-agility options that take the guesswork out of channel configuration. With frequency agility, the access point automatically scans the area and selects the least-congested channel.

Another feature that simplifies deployment and also contributes to a lower cost of ownership is inline power over Ethernet. With inline power, the access point draws operating power from a powered Ethernet port on a device like a switch, so the access point does not have to be located near an electrical outlet.