Cerio OW-400 A1 User Manual page 108

multicast applications.
Fragmentation Threshold: Fragmentation Threshold is one more parameter which is given in
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all stations and Access points. Fine tuning Fragmentation Threshold parameter can result in
good throughput but not using it properly can results in low throughput. In simple words it
does the same thing which MTU do in Ethernet. Both are different parameters but the work
done is same, it fragments the data packets.
Fragmentation threshold will be used when we have more data packet size to be transmitted
and we have less fragment threshold value. Let's say from Ethernet we have to send 1400 byte
packet but the fragmentation threshold is set as 400. In this case when the packet is to be
transmitted on air it will fragment the packet in to 4 small packet 400+400+400+200 and send
on air. This includes MAC header+ frame body and CRC so 400 byte will be in total including
headers. This helps in increasing the throughput. The default is 2346.
RTS Threshold: TRTS Threshold is in the range of 1~2347 byte. The default is 2347 byte.
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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, this function is "Enabled". Disabling will automatically use the
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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.
IGMP Snooping: The process of listening to Internet Group Management Protocol (IGMP)
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network traffic. The feature allows a network switch to listen in on the IGMP conversation
between hosts and routers. By listening to these conversations the switch maintains a map of
which links need which IP multicast streams. Multicasts may be filtered from the links which do
not need them and thus controls which ports receive specific multicast traffic.
Greenfield: In wireless WLAN technology, greenfield mode is a feature of major components of
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the 802.11n specification. The greenfield mode feature is designed to improve efficiency by
eliminating support for 802.11b/g devices in an all draft-n network. In greenfield mode the
network can be set to ignore all earlier standards.
RF on/off by schedule: Administrator can apply Time Policy to on or off wireless
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Location Tracking Log: The system can detect the signal strength of the wireless client to
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determine the location of the Access Point and send to database.
Click "Save" button to save your set function. Then click "Reboot" button to activate your changes.
signal.
V4.0