AT-TQ2403 Management Software User's Guide

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802.11a Turbo

IEEE 802.11a Turbo is a proprietary variant of the 802.11a standard from Atheros Communications. It supports accelerated data rates ranging from 6 to 108Mbps. Atheros Turbo 5 GHz is IEEE 802.11a Turbo mode. Atheros Turbo 2.4 GHz is IEEE 802.11g Turbo mode.

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.

802.11d

IEEE 802.11d defines standard rules for the operation of IEEE 802.11 wireless LANs in any country without reconfiguration. PHY requirements such as provides frequency hopping tables, acceptable channels, and power levels for each country are provided. Enabling support for IEEE 802.11d on the access point causes the AP to broadcast which country it is operating in as a part of its beacons. Client stations then use this information. This is particularly important for AP operation in the 5GHz IEEE 802.11a bands because use of these 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 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.

802.11h

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. TCP 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.