Sercomm UB812EN, Руководство пользователя

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Wireless USB Adapter User Guide
24
Channels
The Wireless Channel sets the radio frequency used for communication.
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Access Points use a fixed Channel. You can select the Channel used. This allows you to
choose a Channel which provides the least interference and best performance. In the USA
and Canada, 11 channels are available. If using multiple Access Points, it is better if adja-
cent Access Points use different Channels to reduce interference.
•
In "Infrastructure" mode, Wireless Stations normally scan all Channels, looking for an
Access Point. If more than one Access Point can be used, the one with the strongest signal
is used. (This can only happen within an ESS.)
•
If using "Ad-hoc" mode (no Access Point), all Wireless stations should be set to use the
same Channel. However, most Wireless stations will still scan all Channels to see if there
is an existing "Ad-hoc" group they can join.
WEP & WPA-PSK
Both WEP and WPA-PSK are standards for encrypting data before it is transmitted.
This is desirable because it is impossible to prevent snoopers from receiving any data which is
transmitted by your Wireless Stations. But if the data is encrypted, then it is meaningless
unless the receiver can decrypt it.
WPA-PSK is a later standard than WEP, and is more secure.
WPA2-PSK
This is a later version of WPA (WPA-PSK). The major change is the use of AES (Advanced
Encryption System) for protecting data. AES is very secure, considered to be unbreakable. The
PSK (Pre-shared Key) must be entered on each Wireless station.
If WPA2-PSK is used, the Wireless Stations and the Access Point must have the same
settings for each of the following:
WPA2 PSK
(Pre-shared Key)
Enter the same value on every station and the AP. The PSK
must be from 8 to 63 characters in length. The 256Bit key
used for the actual encryption is derived from this key.
Encryption The same encryption method must be used. The most
common encryption method is TKIP. Another widely-
supported method is AES.