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Gateway 7001 Series User Manual

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802.11b

IEEE 802.11b (

IEEE Std. 802.11b-1999

) is an enhancement of the initial

802.11 PHY

to

include 5.5 Mbps and 11 Mbps data rates. It uses direct sequence spread spectrum (DSSS)
or frequency hopping spread spectrum (FHSS) in the 2.4 GHz ISM band as well as
complementary code keying (CCK) to provide the higher data rates. It supports data rates
ranging from 1 to 11 Mbps.

802.11e

IEEE 802.11e is a developing

IEEE

standard for

MAC

enhancements to support

QoS

. It

provides a mechanism to prioritize traffic within

802.11

. It defines allowed changes in the

Arbitration Interframe Space, a minimum and maximum Contention Window size, and
the maximum length (in kµsec) of a burst of data.

IEEE 802.11e is still a draft

IEEE

standard (most recent version is D5.0, July 2003). A

currently available subset of 802.11e is the Wireless Multimedia Enhancements (

WME

)

standard.

802.11f

IEEE 802.11f (

IEEE Std. 802.11f-2003

) is a standard that defines the inter access point

protocol (

IAPP

) for access points (wireless hubs) in an extended service set (

ESS

). The

standard defines how access points communicate the associations and reassociations of
their mobile stations.

802.11g

IEEE 802.11g (

IEEE Std. 802.11g-2003

) is a higher speed extension (up to 54 Mbps) to the

802.11b PHY

, while operating in the 2.4 GHz band. It uses orthogonal frequency division

multiplexing (OFDM). It supports data rates ranging from 1 to 54 Mbps.

802.11i

IEEE 802.11i is a developing

IEEE

standard for security in a wireless local area network

(

WLAN

). It defines enhancements to the

MAC

Layer to counter the some of the weaknesses

of

WEP

. 802.11i will incorporate

802.1x

and stronger encryption techniques, such as

Advanced Encryption Standard (

AES

).

IEEE 802.11i is still a draft

IEEE

standard (most recent version is D5.0, August 2003). A

currently available subset of 802.11i is the

Wi-Fi

Protected Access (

WPA

) standard.