SMC Networks WBR14S-N3 - annexe 1 Manual page 58

5
System Configuration
• Beacon Interval – The rate at which beacon signals are transmitted from the
access point. The beacon signals allow wireless clients to maintain contact with the
access point. They may also carry power-management information. (Range:
20-999 TUs; Default: 100 TUs)
• Data Beacon Rate (DTIM) – The rate at which stations in sleep mode must wake
up to receive broadcast/multicast transmissions. Known also as the Delivery Traffic
Indication Map (DTIM) interval, it indicates how often the MAC layer forwards
broadcast/multicast traffic, which is necessary to wake up stations that are using
Power Save mode. The default value of 2 indicates that the access point will save
all broadcast/multicast frames for the Basic Service Set (BSS) and forward them
after every second beacon. Using smaller DTIM intervals delivers broadcast/
multicast frames in a more timely manner, causing stations in Power Save mode
to wake up more often and drain power faster. Using higher DTIM values reduces
the power used by stations in Power Save mode, but delays the transmission of
broadcast/multicast frames. (Range: 1-255 beacons; Default: 1 beacon)
• Fragment Threshold – Configures the minimum packet size that can be
fragmented when passing through the access point. Fragmentation of the PDUs
(Package Data Unit) can increase the reliability of transmissions because it
increases the probability of a successful transmission due to smaller frame size. If
there is significant interference present, or collisions due to high network utilization,
try setting the fragment size to send smaller fragments. This will speed up the
retransmission of smaller frames. However, it is more efficient to set the fragment
size larger if very little or no interference is present because it requires overhead
to send multiple frames. (Range: 256-2346 bytes; Default: 2346 bytes)
• RTS Threshold – Sets the packet size threshold at which a Request to Send
(RTS) signal must be sent to a receiving station prior to the sending station starting
communications. The access point sends RTS frames to a receiving station to
negotiate the sending of a data frame. After receiving an RTS frame, the station
sends a CTS (clear to send) frame to notify the sending station that it can start
sending data. If the RTS threshold is set to 0, the access point always sends RTS
signals. If set to 2347, the access point never sends RTS signals. If set to any other
value, and the packet size equals or exceeds the RTS threshold, the RTS/CTS
(Request to Send / Clear to Send) mechanism will be enabled. The access points
contending for the medium may not be aware of each other. The RTS/CTS
mechanism can solve this "Hidden Node Problem." (Range: 0-2347 bytes)
• TX Power – Adjusts the power of the radio signals transmitted from the access
point. The higher the transmission power, the farther the transmission range.
Power selection is not just a trade off between coverage area and maximum
supported clients. You also have to ensure that high-power signals do not interfere
with the operation of other radio devices in the service area.
• Short Preamble – Enables the length of the signal preamble that is used at the
start of a data transmission. (Default: Disable)
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