User's Manual

Chapter 6 Wireless LAN
NWA1121-NI User’s Guide
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Pream ble Type Select Dynam ic to have the AP automatically use short preamble when wireless adapters
support it, otherwise the AP uses long preamble.
Select Long if you are unsure what pream ble m ode the wireless adapters support, and to
provide more reliable comm unications in busy wireless networks.
RTS/ CTS
Threshold
(Request To Send) The threshold (number of bytes) for enabling RTS/ CTS handshake.
Data with its fram e size larger than this value will perform the RTS/ CTS handshake.
Setting this attribute to be larger t han the maximum MSDU (MAC service data unit) size
turns off the RTS/ CTS handshake. Set ting this attribute to its smallest value (1) turns on
the RTS/ CTS handshake.
Fragmentation The threshold (number of bytes) for the fragm entation boundary for directed messages. I t
is the m aximum data fragment size that can be sent.
Extension
Channel
Protection Mode
You can use CTS to se lf or RTS- CTS protection mechanism to reduce conflicts with other
wireless networks or hidden wireless clients. The throughput of RTS- CTS is m uch lower
than CTS t o se lf. Using this m ode may decrease your wireless perform ance.
A- MPDU
Aggregation
This field is available only when 8 0 2 .1 1 b/ g/ n is selected as the W ireless Mode.
Select to enable A-MPDU aggregation.
Message Protocol Data Unit ( MPDU) aggregation collects Ethernet fram es along with their
802.11n headers and wraps them in a 802.11n MAC header. This m ethod is useful for
increasing bandwidth throughput in environments that are prone to high error rates.
Short GI This field is available only when 8 0 2 .1 1 b/ g/ n is selected as the W ire le ss M ode. Select
Ena bled to use Shor t GI (Guard Interval). The guard interval is the gap introduced
between data transm ission from users in order to reduce interference. Reducing t he GI
increases data t ransfer rates but also increases interference. I ncreasing the GI reduces
data transfer rates but also reduces interference.
MCS Rate The MCS Ra t e table is available only when 8 0 2 . 1 1 b/ g/ n is selected in the W irele ss
Mode field.
IEEE 802.11n supports many different data rates which are called MCS rates. MCS stands
for Modulation and Coding Schem e. This is an 802.11n feature that increases the wireless
network perform ance in terms of throughput.
For each MCS Rate (0-15), select either Enabled to have the NWA1121-NI use the data
rate.
Clear t he Enabled check box if you do not want the NWA1121-NI to use the data rate.
Turn on the Aut o option to have the NWA1121-NI set the data rates autom atically to
optim ize the throughput.
Note: You can set the NWA1121-NI to use up to four MCS rates at a time.
Apply Click Apply to save your changes.
Cancel Click Cancel to begin configuring this screen afresh.
Table 11 Wireless LAN > Wireless Settings: Repeater (continued)
LABEL DESCRIPTION