When companies talk about mobility, they're often referring to employees working from their homes or from airports or hotel rooms.

s of mobility can also be found right at a company's headquarters.

Just inside the office, companies with wireless networks can keep up with network moves, additions and changes with ease. They can support temporary workgroups; enable Internet access in conference rooms or other meeting spaces; change locations without re-wiring buildings and much more.

WLANs make it affordable and easy to get all the benefits of mobility without ever leaving the office.

In the past, WLANs might have seemed unfamiliar and even exotic to a small business. Today, the technology has become so common that people are installing WLANs in their homes.

However, businesses that recognize the value of WLAN might still be wondering about things like security and reliability. Here are some of the most important characteristics of a worry-free WLAN solution.

1. Security

While the benefits of WLANs are indisputable, small companies may still be concerned about the security risks associated with letting business-critical data float about in the air.

This fear is understandable: With a WLAN, data is broadcast over the air using radio waves. This means that any WLAN-enabled computing device within reach of a wireless access point can receive data transmitted to or from the access point.

Because radio waves travel through ceilings, floors, and walls, transmitted data can reach the wrong recipients on different floors or even outside the building. Intruders can use unsecured access points to get into corporate resources and launch denial-of-service attacks that can bog down servers with bogus requests and prevent user access to data and applications. Without stringent security in place, installing a WLAN can be the equivalent of putting Ethernet ports everywhere, including the company parking lot.

Most first-generation WLANs are based on service set identifiers (SSIDs) and manual Wired Equivalent Privacy (WEP) key management. These security mechanisms are time-intensive to administer and not all that secure, in part because the static encryption keys used in WEP rarely change, leaving hackers plenty of time to decode them.

However, as WLANs have become popular, the technology has advanced quickly. In particular, standards bodies and vendors have worked diligently to develop more robust security mechanisms to ensure that companies large and small can use wireless technology with confidence.

The safest WLANs now offer a combination of security capabilities, including dynamic encryption keys (also called dynamic session key management) and centralized key management.

2. Interoperability and reach

Sometimes a WLAN is deployed instead of a wired local-area network (for example, in the case of an older building that is not easy to re-cable). However, there are also times when a WLAN is deployed alongside an existing wired LAN. A prime example is deploying WLANs for meeting or common areas such as lobbies and conference rooms, or providing connectivity with a remote site like a factory, warehouse, or sales office that may be difficult or too expensive to hard-wire.

Wireless bridges are ideal for connecting multiple buildings without expensive lines or cables. Even sites that are separated by obstacles (such as freeways or parking lots) can be bridged wirelessly.

3. Reliability

Reliability is important in conventional office settings, of course, but it is particularly important in environments like warehouses and factories that may lack the amenities of air conditioning or heat and present more obstacles (e.g., pipes, machinery) than office areas.

To ensure reliable performance in these environments, look for the ability to configure the radio transmit power to meet specific coverage requirements and minimize interference, as well as optional antennas to increase the range of the WLAN.

4. Manageability

It is not at all uncommon for companies to have both a traditional wired LAN and a WLAN — for example, a wired LAN in the office and a WLAN in a remote location. If you have both types of networks, it's important to make sure that the two types of LANs are compatible and manageable as though they were one network. This makes it easier and more cost-effective to administer security policies across both network types, as well as to handle routine troubleshooting