Bob Egan's weekly column
October 7, 2004 issue
We believe that in 2005, 80% of all enterprises with wireless installations will begin suffering periodic, chronic network service issues due to interference resulting from the lack of effective spectrum-management policies. The variety and number of devices using unlicensed wireless spectrum affects enterprises in two ways: 1) increased potential for interference and service degradation and/or outages, and 2) the need for proactive policies and skills sets to identify potential problems before they impair productivity. Considering that more than 25% of enterprises already use some form of wireless and more then 40% of all laptops are shipped with integrated Wi-FI, we expect that interference risk management will become critical to control total cost of ownership (TCO) and improve network services reliability in 2005 and beyond.
Laptops and PDAs are no longer the only enterprise devices that use unlicensed wireless technologies such as Bluetooth and Wi-Fi. (The 802.11b version of Wi-Fi uses the same 2.4 GHz band as Bluetooth, increasing the potential for interference.) So do some printers, projectors and white boards. Enterprises that fail to recognize the potential for interference will waste resources and increase their TCO by trying to track down and fix problems that could have been prevented through planning and policy.
Enterprises are well advised to develop a comprehensive inventory of all workplace devices that use wireless technologies, including those that don't fall under the purview of the IT department. CIOs and IT managers should develop companywide policies and employee-education plans to avoid problems – now and in the future.
Enterprises should heed the following guidelines when managing their facility's wireless environment:
- Identify all wireless devices. Look beyond obvious devices such as PDAs and laptops. For example, some projectors use Wi-Fi, while some electronic white boards and printers use Bluetooth. If the company's AV department installs and manages those products, the IT department may go on a wild-goose chase, wasting time and resources by assuming that only an access point could be the source of interference. Microwave ovens and cordless phones can also be sources of interference.
- Define acceptable devices. Look beyond obvious unauthorized devices such as employee-supplied "rogue" access points. For example, an employee may have installed a Bluetooth or Wi-Fi printer adapter that functions properly but interferes with nearby devices.
- Educate employees. Employees may not recognize the potential for interference created by do-it-yourself wireless projects. Enterprises are well advised to create comprehensive guidelines – in plain English – that identify the risks and penalties for using unauthorized devices.
- Look for quality, user-friendly products. Many PDAs and some laptops feature a switch that lets users turn wireless on and off rather than wading through menus or the system tray. If wireless can be shut off with just the flick of a switch, employees are more likely to comply with company policies, as well as airline restrictions, so they can continue to work instead of just powering down or flouting the rules. At the same time, look for enterprise-class infrastructure products with ample management and quality-of-service features, such as access points with the ability to adjust signal power. Inexpensive, consumer-grade products may save money up front, but can wind up costing more in the long run if they cause or are susceptible to interference.
- Plan ahead. Situations that aren't problematic now may be in the future. For example, current levels of interference may be unacceptable with voice, which is less tolerant of latency and packet retransmission than data is. So if voice over Wi-Fi is a possibility, consider migrating to 802.11a, which uses less-congested spectrum (5.8 GHz) than 802.11b/g and offers more channels.