Monday, December 30, 2013

Networking: 802.11 WiFi Standards (Updated)

Are you confused by all the 802.11 WiFi "alphabet soup of letter name" standards, such as 802.11a, 802.11b, 802.11g, etc? Currently 802.11n  is the most popular standard, and its backwards compatible with 802.11b, and 802.11g.

Here is a brief breakdown of the different 802.11 standards; including: speed, frequency, and the date it was ratified as a standard:
  • 802.11: up to 2Mbps, uses the 2.4GHz frequency (Finalized: 1997)
  • 802.11b: up to 11Mbps, uses the 2.4GHz frequency (Finalized: 7/1999)
  • 802.11a: up to 54Mbps, uses the 5GHz frequency (Finalized: 7/1999)
  • 802.11g: up to 54Mbps, uses the 2.4GHz frequency (Finalized: 6/2003)
  • 802.11n: up to 150Mbps+, uses the 2.4Ghz and 5GHz frequency (Finalized: 10/2009)
    • Utilizes MIMO (Multiple-Input Multiple-Output), uses multiple transmitters and receivers antennas to allow for increased data throughput.
    • Some Wi-Fi cards and routers can support speeds of 300Mbps when utilizing a feature called 'channel bonding' (if its supported in the networking equipment) and not running into interference from other nearby wireless networks.
  • 802.11ac: up to 866Mbps+, uses the 5GHz frequency (Still in draft)
For more information see the following Wikipedia article.

From: Wikipedia
  • All 802.11 Wi-Fi hotspots only can run as fast as the slowest device on the network.  For example, if you have a 802.11n wireless network with 5 people communicating at 150Mbps. Then if someone brings 802.11b device on the network the Wireless Access Point will slow down to 11Mbps to support the slower device. 
  • 2.4GHz equipment can incur interference from microwave ovens, cordless phones, and other appliances using the same radio signal frequency range.
  • The higher frequency 5GHz equipment signals has more difficulty penetrating walls and other obstructions.

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