Cerio OW-200N2, User Manual

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User’s Manual
500mW eXtreme Power 11Na Outdoor Bridge
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„ 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.
„ 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.
„ 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.
„ Tx Burst : By default, it’s “ Enable ”. To Disable is to deactivate Tx Burst.
With TX burst enabled, AP will send many packets in a burst, without collision detection and RTS/CTS for each packet. TX
Burst have better throughput but cause interference with other APs in channel.
„ Pkt_Aggregate : By default, it's “ Enable ”
Increase efficiency by aggregating multiple packets of application data into a single
transmission frame. In this way, 802.11n networks can send multiple data packets with the fixed
overhead cost of just a single frame.
„
IEEE802.11H (DFS) : By default, it's “ Disable ”. To Enable is to use IEEE802.11H(DFS)
With DFS(Dynamic Frequency Selection) enabled, radio is operating on one of the following
channels, the wireless device uses DFS to monitor the operating frequency and switch to another
frequency or reduce power as necessary: