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, and replaced the older 802.11b ("B") standard, later eventually replaced by 802.11n ("N") and newer standards.

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 cannot achieve the 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) that was originally introduced to Wi-Fi with 802.11a ("A"). OFDM technology enabled G (and A) to achieve significantly greater 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 greater signal range than what A could offer.

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

G was specially designed for cross compatibility. What this means is that devices can join wireless networks even when the wireless access point runs a different Wi-Fi version. Even the newest 802.11ac Wi-Fi equipment today 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 usages.

They can be found inexpensively through both retail and secondhand sales outlets. However, 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.