WiFi Wireless Ethernet Adapter User Guide ASR-102, ACR-201

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applied to other Wi-Fi radios, however, may result in very different keys. For this
reason, clicking the Apply button after entering the pass-phrase will cause the 4
sets of keys being temporarily displayed under “Manual Entry” as if they were
entered manually. (See screen-shots #9 and #10, the display in screen-shot #10
is dimmed and not modifiable.) These displayed keys can be copied down and
manually entered for radios other than AirEZY-2411-BT to assure interoperability.
Clicking the button or switching to another tab and then return will cause the keys
to be hidden again. Up to 64 characters can be entered for the pass-phrase.
“Manual Entry” requires typing in all four keys. 5 bytes (10 characters) need to be
entered if the 64-bit encryption option is chosen—the other 8 bytes (16
characters are dimmed and not modifiable). 13 bytes (26 characters) need to be
entered if the 128-bit encryption option is chosen.
Use Dynamic WEP Key: The
encryption scheme adopted by the
802.11 standard is static in nature.
Such static scheme has been proven
to be vulnerable to cracking. Internet
downloadable software such as
Airsnort can crack a static encryption
key in as short a time as 15 min.
AirEZY-2411-BT counters such
security hole by generating and
distributing fresh WEP keys in time
intervals less than 12 min.. This
capability is built on top of the default
key scheme. The default keys (64-bit
or 128-bit) are still set up in the same
manner described above. Except that
Key #4 is no longer available as a
selection for transmission (see
Transmission Key Sel below). The
default keys in this situation are only
used in the authentication process. A Station must respond to an authentication
challenge with one of the default keys in the usual manner defined by the 802.11
standards. Upon successful authentication, the AP uses one of the default keys
to send the seed of the Current WEP key (the one generated by the AP and has
no relation to any of the default keys) to the Station. From that point on, the data
exchanged between the AP and the Station are encrypted with this AP controlled
WEP key. In a time interval shorter than 12 min., the seed of a fresh key is sent
to the Station encrypted with the Current Key. The static default keys are NOT
used for data encryption when the dynamic WEP key is enabled. Note that the
highest level of Access Control (Hide SSID, Match SSID, Use Allowed List)
should be selected on the AP in order to benefit the most from the use of the
Dynamic WEP Key feature.
Transmission Key Sel: (Transmission Key Selection) One of the 4 default keys
needs to be selected for transmitting data frames. The radio can de-encrypt
received data encrypted in any one of the four default keys, but it uses only one
Screen-Shot #11