D-Link DWL-8500AP, Руководство администратора

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D-Link Unified Access Point Administrator’s Guide
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frequencies varies a great deal from one country to
another.
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 (
WMM ) 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 re-associations 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.
802.11h
IEEE 802.11h is a standard used is to resolve the
issue of interference which was prevalent in 802.11a.
The two schemes used to minimize interference in
802.11h are Transmit Power Control (TPC) and
Dynamic Frequency Selection (DFS). DFS detects
other APs on the same frequency and redirects these
to another channel. TPC reduces the network
frequency output power of the AP, thus reducing the
chance of any interference. This is a required
standard in Europe, Japan, and the U.S.
802.11i
IEEE 802.11i is a comprehensive IEEE standard for
security in a wireless local area network ( WLAN )
that describes Wi-Fi Protected Access 2 ( WPA2 ). It
defines enhancements to the MAC Layer to counter
the some of the weaknesses of WEP . It incorporates
stronger encryption techniques than the original Wi-
Fi Protected Access ( WPA ), such as Advanced
Encryption Standard ( AES ).
The original WPA , which can be considered a subset
of 802.11i, uses Temporal Key Integrity Protocol
(
TKIP ) for encryption. WPA2 is backwards-
compatible with products that support the original
WPA
IEEE 802.11i / WPA2 was finalized and ratified in
June of 2004.
802.11j
IEEE 802.11j standardizes chipsets that can use both
the 4.9 and 5 GHz radio bands according to rules
specified by the Japanese government to open both
bands to indoor, outdoor and mobile wireless LAN
applications. The regulations require companies to
adjust the width of those channels. IEEE 802.11j
allows wireless devices to reach some previously
unavailable channels by taking advantage of new
frequencies and operating modes. This is an attempt
to mitigate the crowding on the airwaves, and has
tangential relationships to IEEE 802.11h.
802.11k
IEEE 802.11k is a developing IEEE standard for
wireless networks ( WLAN s) that helps auto-manage
network Channel selection, client Roaming , and
Access Point (AP) utilization. 802.11k capable
networks will automatically load balance network
traffic across APs to improve network performance
and prevent under or over-utilization of any one AP.
802.11k will eventually complement the
802.11e
quality of service ( QoS ) standard by ensuring QoS
for multimedia over a wireless link.
802.1p
802.1p is an extension of the IEEE 802 standard and
is responsible for QoS provision. The primary
purpose of 802.1p is to prioritize network traffic at
the data link/ MAC layer. 802.1p offers the ability to
filter multicast traffic to ensure it doesn’t increase