Chapter 6 Wireless LAN

Table 14 Wireless LAN > Wireless Settings: MBSSID (continued)

LABEL

DESCRIPTION

Preamble Type

Select Dynamic 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 preamble mode the wireless adapters support, and to

 

provide more reliable communications in busy wireless networks.

 

 

RTS/CTS

(Request To Send) The threshold (number of bytes) for enabling RTS/CTS handshake.

Threshold

Data with its frame size larger than this value will perform the RTS/CTS handshake.

 

Setting this attribute to be larger than the maximum MSDU (MAC service data unit) size

 

turns off the RTS/CTS handshake. Setting this attribute to its smallest value (1) turns on

 

the RTS/CTS handshake.

 

 

Extension

You can use CTS to self or RTS-CTSprotection mechanism to reduce conflicts with other

Channel

wireless networks or hidden wireless clients. The throughput of RTS-CTSis much lower

Protection Mode

than CTS to self. Using this mode may decrease your wireless performance.

 

 

A-MPDU

This field is available only when 802.11n, 802.11b/g/n, 802.11a/n or 802.11a/n/ac

Aggregation

is selected as the Wireless Mode.

 

Select to enable A-MPDU aggregation.

 

Message Protocol Data Unit (MPDU) aggregation collects Ethernet frames along with their

 

802.11n headers and wraps them in a 802.11n MAC header. This method is useful for

 

increasing bandwidth throughput in environments that are prone to high error rates.

 

 

Short GI

This field is available only when 802.11n, 802.11b/g/n, 802.11a/n or 802.11a/n/ac

 

is selected as the Wireless Mode.

 

Select Enabled to use Short GI (Guard Interval). The guard interval is the gap

 

introduced between data transmission from users in order to reduce interference.

 

Reducing the GI increases data transfer rates but also increases interference. Increasing

 

the GI reduces data transfer rates but also reduces interference.

 

 

MCS Rate

The MCS Rate table is available only when 802.11n, 802.11b/g/n or 802.11a/n or

 

802.11a/n/ac is selected in the Wireless Mode field.

 

IEEE 802.11n supports many different data rates which are called MCS rates. MCS stands

 

for Modulation and Coding Scheme. This is an 802.11n feature that increases the wireless

 

network performance in terms of throughput.

 

For each MCS Rate (0-15), select either Enabled to have the NWA use the data rate.

 

Clear the Enabled check box if you do not want the NWA to use the data rate.

 

Turn on the Auto option to have the NWA set the data rates automatically to optimize the

 

throughput.

 

Note: You can set the NWA 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.

 

 

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NWA1120 Series User’s Guide