Vivato VA4200, User Manual

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Copyright © 2004-2005, Vivato, Inc.
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 AP/Bridge protocol ( IAPP ) for
AP/Bridges (wireless hubs) in an extended service set ( ESS ). The standard defines how AP/Bridges
communicate the associations and re-associating 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.
802.1Q
IEEE 802.1Q is the IEEE standard for Virtual Local Area Networks ( VLAN s) specific to wireless
technologies. (See http://www.ieee802.org/1/pages/802.1Q.html .)
The standard addresses the problem of how to break large networks into smaller parts to prevent
broadcast and multicast data traffic from consuming more bandwidth than is necessary. 802.11Q also
provides for better security between segments of internal networks. The 802.1Q specification provides a
standard method for inserting VLAN membership information into Ethernet frames.
AP/Bridge
A AP/Bridge is the communication hub for the devices on a WLAN , providing a connection or bridge
between wireless and wired network devices. It supports a Wireless Networking Framework called
Infrastructure Mode .
When one AP/Bridge is connected to wired network and supports a set of wireless stations, it is referred to
as a basic service set (
BSS ). An extended service set ( ESS ) is created by combining two or more BSSs.
Ad hoc Mode
Ad hoc mode is a Wireless Networking Framework in which stations communicate directly with each other.
It is useful for quickly establishing a network in situations where formal infrastructure is not required.
Ad hoc mode is also referred to as peer-to-peer mode or an independent basic service set ( IBSS ).