User Manual

37
The RTS Threshold Value should remain at its default setting of 2,432. A pre-
amble is a signal used to synchronize the transmission timing between two or
more systems. A series of transmission pulses is sent before the data to indicate
that “someone is about transmit data.” This ensures that systems receiving the
information correctly when the data transmission starts.
Security is used for WEP only. By selecting Deny Unencrypted Data
Frames, all unencrypted data will not be seen. For Authentication Type, you
may choose between Open System or Shared Key.
Shared Key is when both the sender and recipient share a secret key. Both
units use this key for an extended length of time, sometimes indefinitely.
Any eavesdropper that discovers the key may decipher all packets until the
key is changed.
Open System, the default setting, is when the sender and the recipient do
not share a secret key. Each party generates its own key-pair and asks the
receiver to accept the (usually randomly) generated key. Once accepted,
this key is used for a short time only; then a new key is generated and
agreed upon.
The Preamble Type
should be set to Short (if
the network environment
is “noisy”) or Long (if the
environment is clear).
Click OK to complete the
configuration.
ABOUT
The About screen (Figure
7-7) shows the release
information for the Driver
Version, Configuration
Utility Version, and
Firmware Version
Figure 7-7
In order to enable 128-bit WEP encryption, choose 128 Bits in the drop-down
box. In the drop-down box near the bottom right-hand corner of the page,
choose which Default Tx Key will be used for the encryption. By default, Key
1 will be used. In the box corresponding to the default you chose, enter a hexa-
decimal number that the encryption algorithm will be based on. Click Apply
Changes when you are done.
ADVANCED
The Advanced screen (Figure 7-6) allows you to set the Fragmentation
Threshold, the RTS/CTS Threshold, and the Preamble Type. The
Fragmentation Threshold Value indicates how much of the network resources
is devoted to recovering packet errors. The value should remain at its default
setting of 2,432. If you experience high packet error rates, you can decrease this
value but it will likely decrease overall network performance. Only minor mod-
ifications of this value are recommended.
Network PC Card
Figure 7-6
Instant Wireless
Series
38