Wireless Alphabet Soup

First came 802.11b, then 802.11a, followed by 802.11g, and now 802.11n. In this article, we'll demystify 802.11 wireless standards.

802.11b
The Institute of Electrical and Electronics Engineers (IEEE) ratified the 802.11b standard in July 1999. Providing peak data transfer speeds as fast as 10BaseT Ethernet, 802.11b is well suited for Web navigation, e-mail, small office and home networking, and handheld mobile devices.

Pros

  • Low cost – built into many devices and computers.
  • Good range – typically 150-300 feet indoors.
  • Not easily obstructed – transmits well through most walls and barriers.
  • Wide adoption – compatible with most access points and public hotspots.
  • Future proof – compatible with 802.11g and 802.11n.

Cons

  • Interference – crowded 2.4GHz frequency can mean conflicts with Bluetooth devices, cordless phones and even microwave ovens.
  • Slower speed – 11 Mbps maximum throughput.
  • Lower quality of service – poorly suited for Vo-WLAN and other streaming applications.
  • Bottlenecks –users compete for its three channels and 11 Mbps bandwidth.

802.11a
Despite the fact that 802.11a provides about five times 802.11b`s throughput–up to 54 Mbps–and operates on the much less crowded 5GHz band, it hasn’t enjoyed the widespread popularity of the b version, because of its limited range. 802.11a though is much better suited for bandwidth-demanding tasks such as wireless streaming of video, mobile videoconferencing, and voice over WLAN.

Pros

  • Less interference – 5GHz band is less crowded with frequency conflicts.
  • Greater bandwidth – 54Mbps allows for high-speed networking and multimedia streaming.
  • Reduced bottlenecks – can handle more simultaneous users than 802.11b.

Cons

  • Shorter range – 60-90 feet indoors. Less compatible – can't communicate directly with 802.11b/g hardware and most public hotspots.
  • More expensive – more access points are required for similar sized wireless footprint.

802.11g
Like 802.11a, 802.11g offers data speeds up to 54Mbps, however, it operates on the 2.4GHz range and is backward compatible with 802.11b. Approved in June 2003, 802.11g is rapidly replacing 802.11b as users upgrade to the greater bandwidth it offers.

Pros

  • High data speeds – up to 54Mbps. Five times the speed of 802.11b. Good range – typically 150-300 feet indoors.
  • Not easily obstructed – transmits well through most walls and barriers.
  • Highly compatible – communicates with 802.11b devices and most public hotspots.

Cons

  • Interference – on the same crowded 2.4GHz frequency as 802.11b.
  • Cost – more expensive than 802.11b.
  • Bottlenecks – only three channels compared to 802.11a`s eight.

Why choose?
Several manufacturers now offer hybrid 802.11a/b/g access points and cards that eliminate the need to select a single standard. There is, however, the tradeoff of higher initial investment.

802.11n
Just when you thought 802.11 confusion was clearing up, another standard jumps into the fray. Yet to be approved by the IEEE, 802.11n promises to dramatically improve upon the capabilities of other Wi-Fi standards. 802.11n will offer data speeds in excess of 100Mbps (with over 600Mbps predicted) to enable host of high-speed, bandwidth-intensive applications. Fortunately, this standard is also designed from the start to be backward compatible with the other Wi-Fi standards.

Currently, two proposed 802.11n standards—each backed by its own group of industry heavyweights—are vying to become the final spec. This Wi-Fi Planet article discusses the ongoing 802.11n standards campaign.

The 802.11n standard was expected to be ratified by late 2005 at the earliest. But that hasn't deterred several manufacturers from offering "pre-n" hardware.

But wait, there's more!
There are also 802.11d, 802.11i, and a number of other IEEE 802.11 standards. Don't worry though, most of these work behind the scenes to tackle assorted security, maintenance, quality-of-service, and international compatibility issues.

Don't hesitate to call Databranch with your wireless networking questions.  We are Cisco Certified Wireless LAN Specialist and have experience performing wireless site surveys for both large and small businesses.  Contact sales@databranch.com