High-performance IEEE wireless LAN (WLAN) standard. Operates in the unlicensed 5 GHz frequency band. Delivers up to 54 Mbps data transfer rates.

Radio, or Physical Layer (PHY), based on an Orthogonal Frequency Division Multiplexing (OFDM) modulation scheme. Media Access Controller (MAC) based on the standard IEEE 802.11 MAC architecture (consistent across 802.11a, 802.11b and 802.11g).

Availability: Solutions are not widely available from a broad range of companies in many form factors.

Best in class speed: High throughput (up to 54 Mbps) to support heavily-loaded networks and rich multimedia content like HDTV and multiple MPEG-2 (DVD quality) video streams.

Interference: The 5 GHz band is still relatively uncluttered, so there is less interference than in the 2.4 GHz band.

More expensive than 802.11b.

Range: Will deliver significantly less range than 802.11b.

QoS/multimedia support: Standard 802.11 MAC is Ethernet-based and does not support multimedia streams (particularly concurrent streams) well.

Interoperability: 802.11a products are not interoperable with the large and growing base of 802.11b networks.

IEEE WLAN standard. Operates in the unlicensed 2.4 GHz frequency band. Delivers data throughput of 11 Mbps.

PHY is based on a Direct Sequence Spread Spectrum (DSSS) modulation scheme. MAC is based on the standard 802.11 MAC architecture.

Features an interoperability mark called Wi-Fi, which is earned via third party interoperability testing. Wi-Fi certified products will communicate with each other.

Availability: Solutions are widely available, from a broad group of companies and in a variety of forms.

Interoperability: Large and growing installed based of 802.11b networks in businesses and public areas; beginning to emerge in the home as well (802.11b has won the battle with HomeRF).

Cost: Price points for technology and products are rapidly declining.

Adequate Speed: Maximum data rates of 11 Mbps, equivalent to 10BaseT Ethernet. With a multimedia enabled MAC, this speed enables high-speed Internet sharing, CD-quality audio and single MPEG-2 streams.

Range: Offers superior range versus 802.11a; up to 150 feet depending on product and operating environment.

Lack of QoS and multimedia support: Designed for the enterprise, 802.11b is limited in its ability to support rich multimedia. Cannot support concurrent media streams well.

Interference: Susceptible to interferers in the 2.4 GHz band, such as microwave ovens and cordless phones.

Complexity: Most 802.11b products are hard to install and reconfigure.

Range Degradation: Generally, offers ranges up to 150 feet, much more than 802.11a. In most cases, however, data rates begin to drop back (to 5.5 Mbps, then 2 Mbps, then 1 Mbps) far in advance of the maximum range, and many products can't reach 150 feet at any speed.

2.4 GHz physical layer specification that offers faster data rates than 802.11b (up to 54 Mbps).

Uses an OFDM PHY operating in the 2.4 GHz band. MAC based on standard 802.11 MAC architecture.

Can interoperate with 802.11b nodes.

Speed: 802.11g's higher data rates versus 802.11b enable both richer content to be sent across the network, as well as enabling more concurrent streams.

Interoperability: 802.11g is interoperable with the large growing installed base of 802.11b networks.