Wireless/Redundant Edge Services xl Module Management and Configuration Guide WS.02.xx and greater

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Radio Port Configuration
Configuring Radio Settings
Stations can avoid transmitting at the same time by exchanging RTS and Clear
to Send (CTS) packets with the RP. A wireless station sends an RTS packet to
notify the radio that it would like to transmit. If the channel is clear, the radio
sends a CTS packet to the requesting station. This procedure clears the air for
a specific transmission when many stations may be contending for transmis-
sion time.
Employing RTS/CTS exchanges can result in fewer data collisions and better
communication with hidden or obscured nodes. However, the RTS/CTS
exchange itself consumes bandwidth and can increase latency and reduce
data-frame throughput.
You can set an RTS threshold size, in bytes, which determines when an RTS/
CTS exchange must be made. If a station wants to send a data frame larger
than the threshold size, it must exchange RTS/CTS frames with the radio.
Otherwise, it can follow typical 802.11 procedures.
It is important to consider the needs of your wireless network when setting
this threshold. If your network has a high level of wireless traffic, hidden
stations, or interference, you should set a lower RTS. However, if your
network has a relatively low amount of wireless traffic and transmission
contention, you could set a higher RTS to allow a higher data throughput.
To configure the RTS threshold for adopted radios of a particular type,
complete these steps:
1. Select Network Setup > Radio Adoption Defaults and click the
Configuration tab.
2. Select the radio type and click the Edit button.
3. In the RTS Threshold field, enter the data frame size, in bytes, at which a
station must send an RTS frame.
The default threshold is 2,346 bytes, which means that the RTS/CTS
exchange will never be used (because 2,346 bytes is the maximum size for
an 802.11 frame).
4. Click the OK button.