Cerio OW-200N2, User Manual

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User’s Manual
500mW eXtreme Power 11Na Outdoor Bridge
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6.4.2 DTIM Interval : The DTIM interval is in the range of 1~255. The default is 1.
DTIM is defined as Delivery Traffic Indication Message. It is used to notify the
wireless stations, which support power saving mode, when to wake up to receive
multicast frame. DTIM is necessary and critical in wireless environment as a
mechanism to fulfill power-saving synchronization.
A DTIM interval is a count of the number of beacon frames that must occur before the
access point sends the buffered multicast frames. For instance, if DTIM Interval is
set to 3, then the Wi-Fi clients will expect to receive a multicast frame after receiving
three Beacon frame. The higher DTIM interval will help power saving and possibly
decrease wireless throughput in multicast applications.
6.4.3 Fragment Threshold : The Fragment Threshold is in the range of 256~2346 byte.
The default is 2346 byte.
Each Wi-Fi packet can be divided into smaller packets, marked with a sequential
fragment number and re-assemble in the receiving ends. The purpose is to make a
short frame, instead of long frame, transmitting by radio in a heavy noisy environment.
Because of sending smaller frames, corruptions are much less likely to occur. The
pros is obvious, the cons is the overhead for transmission. So, in a clean environment,
higher fragment threshold can be an option to increase throughput.
Fragmentation will be triggered by setting the Fragment Threshold, usually in
Byte-length. Only when the frame size is over the Threshold, fragmentation will take
place automatically.
6.4.4 RTS Threshold : TRTS Threshold is in the range of 1~2347 byte. The default is 2347
byte.
The main purpose of enabling RTS by changing RTS threshold is to reduce possible
collisions due to hidden wireless clients. RTS in AP will be enabled automatically if
the packet size is larger than the Threshold value. By default, RTS is disabled in a
normal environment supports non-jumbo frames.
6.4.5 Short Preamble : By default, it’s “Enable”. To Disable is to use Long 128-bit
Preamble Synchronization field.
The preamble is used to signal "here is a train of data coming" to the receiver. The
short preamble provides 72-bit Synchronization field to improve WLAN transmission
efficiency with less overhead.
6.4.6 Short Slot : By default, it’s “Enable” for educing the slot time from the standard 20