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Wi-Fi: Unplugging devices

Wi-Fi, short for wireless fidelity, refers to wireless local area networks (LANs) that use one of several 802.11 standards.

Wi-Fi, short for wireless fidelity, refers to wireless local area networks, or LANs, that use one of several 802.11 standards. These wireless networks require the installation of a short-range radio tower, or access point, that sends and receives data to and from devices such as a PDA, or personal digital assistant.

These networks allow for the sharing of resources, such as high-speed Internet access or content, by devices with wireless connections. The range of these networks varies depending on obstacles, such as walls or areas of radio interference but can reach up to 300 feet in radius from the access point. Because they are based on wireless technology, Wi-Fi networks can be set up more quickly and easily than wired networks.

The standards for Wi-Fi products are developed by an industry group called the Institute of Electrical and Electronics Engineers, while products certified for interoperability are determined by a group called the Wi-Fi Alliance. The two groups have played key roles in helping popularize Wi-Fi. They create common guidelines for product development and encourage companies to follow those guidelines. Wireless networking as a concept has been around for years, but it wasn't until the technology became easy to use and prices became affordable over the last two to three years that it really became popular.

With the convenience that wireless brings to setting up networks, in addition to the ability to share resources and content so easily, consumers are looking for the feature, and manufacturers are building new products and basing content-sharing strategies around it. Some businesses have been slow to install Wi-Fi networks because of security concerns, but a standard is expected by the middle of next year, and a preliminary specification is available to address immediate needs.

Wi-Fi products are currently based on three standards, 802.11g, 802.11b and 802.11a, which all use unlicensed radio frequencies so that airtime is free. The common guidelines and free airtime have helped encourage both consumers and manufacturers to use products that are based on the standards. Transfer rates between a client and an access point vary depending on the standard used.

Products that use the latest standard, 802.11g, are compatible with products that are based on the older 802.11b standard, because both use similar bands in the 2.4GHz radio spectrum. The 802.11a standard is not compatible with the other standards, because it uses the bands in the less crowded 5GHz range. The 802.11g and the 802.11a standards allow data to be transferred at a maximum speed of 54 megabits per second, while 802.11b is limited to a high of 11 megabits per second--actual rates are slightly less than half the maximum.

While the market for wireless hardware has grown rapidly, the service market, also known as the hot spot market, is still establishing itself but is being helped along by high numbers of products such as notebooks and other portable devices, in which Wi-Fi connectivity is built in. The hot spot market targets business travelers in crowded public places like airports with for-pay access to broadband Internet connections via Wi-Fi networks.

Wi-Fi service providers and network operators are in the process of determining the best pricing models, and some anticipate that it will be bundled with other forms of connectivity such as cellular communications.

The major companies in the Wi-Fi market are service vendors Boingo Wireless, Wayport, T-Mobile USA and Verizon Communications; hardware suppliers include Cisco Systems and its Linksys division, Intel and NetGear.

During the past nine months, the landscape for companies that drive the installation of hot spots has shifted from small start-ups to large landline and wireless carriers. In June 2002, T-Mobile USA was the only major carrier that offered hot spot access, but recently, AT&T Wireless, SBC Communications, Verizon Communications' joint venture Verizon Wireless and Sprint PCS have started or announced plans to enter the market by the end of the year.