What Is 802.11g Wi-Fi?

A historical look at the Wi-Fi technology

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802.11g is an IEEE standard Wi-Fi wireless networking technology. Like other versions of Wi-Fi, 802.11g (sometimes referred to simply as "G") supports wireless local area network (WLAN) communications among computers, broadband routers, and many other consumer devices.

G was ratified in June of 2003, replacing the older 802.11b ("B") standard. 802.11n ("N") and newer standards eventually replaced G.

Over time, the various Wi-Fi network classifications were given different naming conventions. Instead of 802.11g, it retroactively became known as Wi-Fi 3.

How Fast Is 802.11g?

802.11g Wi-Fi supports a maximum network bandwidth of 54 Mbps, significantly higher than the 11 Mbps rating of B and significantly less than the 150 Mbps or greater speeds of N.

Like many other forms of networking, G can't achieve the theoretical maximum rating in practice; 802.11g connections typically hit an application data transfer rate limit between 24 Mbps and 31 Mbps (with the remaining network bandwidth used by overheads of the communication protocol).

How 802.11g Works

G incorporated the radio communication technique called Orthogonal Frequency Division Multiplex (OFDM), which was initially introduced to Wi-Fi with 802.11a ("A"). OFDM technology helped G (and A) achieve significantly higher network performance than B.

Conversely, 802.11g adopted the same 2.4 GHz range of communication frequencies originally introduced to Wi-Fi with 802.11b. Using this frequency gave Wi-Fi devices significantly more powerful signal range than what A could offer.

There are 14 possible channels on which 802.11g can operate, though some are illegal in some countries. The frequencies from channel 1-14 range between 2.412 GHz to 2.484 GHz.

G was designed for cross-compatibility, so devices can join wireless networks even when the wireless access point runs a different Wi-Fi version. Even today's newest Wi-Fi equipment can support connections from G clients using these same 2.4 GHz compatibility modes of operation.

802.11g for Home Networking and Travel

Numerous brands and models of computer laptops and other Wi-Fi devices were manufactured with Wi-Fi radios supporting G. As it combined some of the best elements of A and B, 802.11g became the predominant Wi-Fi standard at a time when the adoption of home networking exploded worldwide.

Many home networks today still operate using 802.11g routers. At 54 Mbps, these routers can keep up with most high-speed home internet connections, including basic video streaming and online gaming.

G-compatible routers can be found inexpensively through both retail and secondhand sales outlets. G networks can reach performance limits quickly when multiple devices are connected and simultaneously active, but this is true for any network that's consumed by too many devices.

In addition to G routers designed for fixed installation in homes, 802.11g travel routers also gained substantial popularity with business professionals and families who needed to share a single wired Ethernet connection among their wireless devices.

G (and some N) travel routers can still be found in retail outlets but have become increasingly uncommon as hotel and other public internet services shift from Ethernet to wireless hotspots.