Formosa XG-520, User Manual

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Fragment Threshold : Fragmentation mechanism is used for improving
the efficiency when high traffic flows along in the wireless network. If
your 802.11g Wireless LAN PC Card often transmit large files in
wireless network, you can enter new Fragment Threshold value to split
the packet. The value can be set from 256 to 2346. The default value is
2346.
RTS Threshold : RTS Threshold is a mechanism implemented to
prevent the “Hidden Node” problem. “Hidden Node” is a situation in
which two stations are within range of the same Access Point, but are
not within range of each other. Therefore, they are hidden nodes for
each other. When a station starts data transmission with the Access
Point, it might not notice that the other station is already using the
wireless medium. When these two stations send data at the same time,
they might collide when arriving simultaneously at the Access Point.
The collision will most certainly result in a loss of messages for both
stations.
Thus, the RTS Threshold mechanism provides a solution to prevent data
collisions. When you enable RTS Threshold on a suspect “hidden
station”, this station and its Access Point will use a Request to Send
(RTS). The station will send an RTS to the Access Point, informing that
it is going to transmit the data. Upon receipt, the Access Point will
respond with a CTS message to all station within its range to notify all
other stations to defer transmission. It will also confirm the requestor
station that the Access Point has reserved it for the time-frame of the
requested transmission.
If the “Hidden Node” problem is an issue, please specify the packet size.
The RTS mechanism will be activated if the data size exceeds the value
you set.
The default value is 2346.
Warning: Enabling RTS Threshold will cause redundant network
overhead that could negatively affect the throughput performance
instead of providing a remedy.
This value should remain at its default setting of 2346. Should you
encounter inconsistent data flow, only minor modifications of this value
are recommended.
Preamble Type : A preamble is a signal used in wireless environment to
synchronize the transmitting timing including Synchronization and Start
frame delimiter. If you want to change the Preamble type into
Long or
Short , please select the mode you need.
Apply Changes : Click to save and apply the current setting.