Like most specifications used for marketing, the 11Mbps or 54Mbps rating is the theoretical maximum.  As such it assumes ideal conditions with no overheads – i.e. one device is transmitting non-stop and the other device is only receiving.  This doesn’t allow for the data being sent in packets, the packet headers, two-way communications, and especially doesn’t allow for radio being a broadcast medium where you have to wait for ‘clear air’ before starting to transmit (like CB radio).

Consequently Wireless networks can never reach the theoretical bandwidth limits. 

  • 802.11b networks typically get 2-5Mbps.
  • 802.11g is usually in the 13-23Mbps range.

Note also that more active wireless devices will result in more packets colliding, and overall speed goes down as you add more wireless devices. On a fairly busy wireless network this affect can be seen with as few as 5 computers.

Wireless provides excellent convenience, but you should use wired connections wherever convenient because they offer much better speed and security.