qpcom QP-WO259GHP, Руководство пользователя

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Frequently Asked Questions (FAQ)
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enabling stations to establish and maintain communications in an orderly fashion.
Beacon Interval represents the amount of time between beacon transmissions.
Before a station enters power save mode, the station needs the beacon interval to
know when to wake up to receive the beacon (and learn whether there are buffered
frames at the access point).
6.13 What is Preamble Type?
There are two preamble types defined in IEEE 802.11 specification. A long
preamble basically gives the decoder more time to process the preamble. All
802.11 devices support a long preamble. The short preamble is designed to
improve efficiency (for example, for VoIP systems). The difference between the two
is in the Synchronization field. The long preamble is 128 bits, and the short is 56 bits.
6.14 What is SSID Broadcast?
Broadcast of SSID is done in access points by the beacon. This announces your
access point (including various bits of information about it) to the wireless world
around it. By disabling that feature, the SSID configured in the client must match the
SSID of the access point.
Some wireless devices don't work properly if SSID isn't broadcast (for example the
D-link DWL-120 USB 802.11b adapter). Generally if your client hardware supports
operation with SSID disabled, it's not a bad idea to run that way to enhance network
security. However it's no replacement for WEP, MAC filtering or other protections.
6.15 What is Wi-Fi Protected Access (WPA)?
Wi-Fi’s original security mechanism, Wired Equivalent Privacy (WEP), has been
viewed as insufficient for securing confidential business communications. A longer-
term solution, the IEEE 802.11i standard, is under development. However, since the
IEEE 802.11i standard is not expected to be published until the end of 2003, several
members of the WI-Fi Alliance teamed up with members of the IEEE 802.11i task
group to develop a significant near-term enhancement to Wi-Fi security. Together,
this team developed Wi-Fi Protected Access.
To upgrade a WLAN network to support WPA, Access Points will require a WPA
software upgrade. Clients will require a software upgrade for the network interface
card, and possibly a software update for the operating system. For enterprise
networks, an authentication server, typically one that supports RADIUS and the
selected EAP authentication protocol, will be added to the network.
6.16 What is WPA2?
It is the second generation of WPA. WPA2 is based on the final IEEE 802.11i
amendment to the 802.11 standard.