Avaya AP-4 User Manual page 25

IEEE 802.11 Specifications
Also in 1999, the IEEE modified the 802.11 standard to support devices
operating in the 5 GHz frequency band. This standard is referred to as
802.11a. 802.11a devices are not compatible with 2.4 GHz 802.11 or
802.11b devices. 802.11a radios use a radio technology called Orthogonal
Frequency Division Multiplexing (OFDM) to achieve data rates of up to
54 Mbits/sec. In addition, Avaya's 802.11a products support an extension
of the 802.11a standard, known as Turbo mode.
Turbo mode is not part of the 802.11a standard but it allows data rates of
up to 108 Mbits/sec. The AP-5 complies with the IEEE 802.11a standard.
Note: With the exception of the radio configuration settings, all of the
information in this user guide applies to both models, unless
otherwise noted.
1-6 Avaya Wireless AP-4/AP-5 User's Guide