From the 802.11 series of standards, the IEEE 802.11b specification allows for the wireless transmission of approximately 11 Mbps of raw data at distances from several dozen to several hundred feet (10 to about 200 meters) over the 2.4 GHz unlicensed band. The distance depends on impediments, materials, and line of sight.

This specification started to appear in commercial form in mid-1999, with Apple Computer's introduction of its AirPort components, manufactured in conjunction with Lucent's WaveLAN division. (The division changed its named to Orinoco and was spun off to the newly formed Agere corporation with a variety of other Lucent assets in early 2001.)

802.11b is an extension of Ethernet to wireless communication, and as such does not place restrictions on the kinds of data that pass over it. It's primarily used for TCP/IP, but can also handle other forms of networking traffic, such as AppleTalk or PC file sharing standards.

PCs and Macs may communicate compatibly over 802.11b, using equipment from a variety of vendors. The client hardware is typically a PC card or a PCI card, although USB and other forms of 802.11b radios are also being introduced. Adapters for PDAs, such as Palm OS and PocketPC based devices are also available.

Each radio may act, depending on software, as a hub or for computer-to-computer transmission, but it's much more common that a WLAN (wireless local area network) installation uses one or more access points, which are dedicated stand-alone hardware with typically more powerful antennae. The access point often includes routing, DHCP server, NAT, and other features necessary for small to large business operation. Similar to access points are residential gateways, a new class of device, which offers similar features but without the advanced management required for corporate networks or high-traffic installations.

As stated, the standard is backward compatible to an earlier series of specifications, known as 802.11, allowing speeds of 1, 2, 5.5 and 11 Mbps on the same transmitters.

The standard is succeeded by 802.11a. This is not a typo. In this one instance, a follows b.

  802.11     Ethernet     TCP/IP

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Record date: 2005.12.10-1234