Wireless/Redundant Edge Services xl Module Management and Configuration Guide WS.01.03 or greater

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Radio Port Configuration
Configuring Radio Settings
To configure 802.11bg radios to support a short preamble, complete the
following steps:
1. Select Network Setup > Radio Adoption Defaults > Configuration, select
the radio type, and click Edit.
2. Check the box next to Support Short Preamble.
3. Click OK.
Setting the RTS Threshold. Your wireless network may have “hidden” sta-
tions: two stations that can each hear RP beacons but cannot hear each other's
transmissions because of a wall or other barrier between them. Because these
stations cannot detect contention from each other, their frames may collide;
valuable transmission time is spent resending data.
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 would like 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 the following steps:
1. Select Network Setup > Radio Adoption Defaults > Configuration, select
the radio type, and click Edit.