wireless 802.11a. 802.11g, 802.11b

  • Both 802.11a and 802.11g operate at up to 54Mbps data rates
  • 802.11a and 802.11g use common 802.11 medium access control (MAC) layer functions

With 802.11 systems, transmission delays are created because of other user traffic is sharing the same channel, the presence of RF interference and the enabling of various configuration settings, such as power management and fragmentation. For example, a wireless mobile device may transmit frames at 48Mbps, but very poor throughput may prevail if the user is operating close to a microwave oven that uses the same chunk of spectrum or if the immediate area is full of wireless users operating VoWLAN phones associated with the same access point.

  • 802.11a and 802.11g operate in different frequency bands – 802.11g is in the 2.4GHz band and 802.11a in is in the 5GHz band
  • 802.11a has much higher total capacity due to a greater number of non-overlapping channels. In fact, current 802.11a access points have eight completely separate channels.
  • 802.11g users encounter substantial decreases in throughput if just one 802.11b device associates with the same access point. (b and g require sam protection mechanism that they cannot be sent IN THE SAME TIME)

 

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