NetComm NB9 User Manual page 42

Fragmentation Threshold
RTS Threshold
DTIM Interval
Beacon Interval
XpressTM Technology
54gTM Mode
54g Protection
WMM (Wi-Fi Multimedia)
1. TM
About Xpress Technology
Xpress TM Technology is a Broadcom innovation that dramatically improves wireless performance for suitably equipped client workstations while ensuring
compatibility with 802.11b and 802.11g devices. Basically, Xpress
very fast data transfer rates with other Xpress
If you are communicating with Xpress
42
Enter a value between 256 (min) and 2346 (max).
A threshold, specifi ed in bytes, that determines whether packets will be
fragmented and at what size. On an 802.11 WLAN, packets that exceed the
fragmentation threshold are fragmented, i.e., split into smaller units suitable
for the circuit size. Packets smaller than the specifi ed fragmentation
threshold value are not fragmented.
If you experience a high packet error rate, try to slightly increase your
'Fragmentation Threshold'. The value should remain at its default setting of
2346 unless you are troubleshooting wireless network issues. Setting the
'Fragmentation Threshold' too low may result in poor performance.
Request To Send, set in bytes, specifi es the packet size beyond which the
WLAN Card invokes its RTS/CTS (Clear To Send) mechanism. Packets that
exceed the specifi ed RTS threshold trigger the RTS/CTS mechanism. The
NIC (Network Interface Card) transmits smaller packet without using RTS/
CTS.
The default setting of 2347 (maximum length) disables RTS Threshold.
Delivery Traffi c Indication Message (DTIM), also known as Beacon Rate.
The entry range is a value between 1 and 65535. A DTIM is a countdown
informing clients of the next window for listening to broadcast and multicast
messages. When the NB9W has buffered broadcast or multicast messages
for associated clients, it sends the next DTIM with a DTIM Interval value.
AP Clients hear the beacons and awaken to receive the broadcast and
multicast messages. The default is 1.
The amount of time between beacon transmissions. Each beacon
transmission identifi es the presence of an wireless client (or access point).
By default, WLAN passively scan all RF channels and listen for beacons
coming from access points to fi nd a suitable access point.
Before a station (wireless client) enters power save mode, the station needs
the beacon interval to know when to wake up to receive the beacon (and
learn whether there are buffered frames at the access point).
The entered value is represented in ms. Default is 100. Acceptable entry
range is 1 to 0xffff (65535).
Select 'enable' to activate in-built Xpress
Select the mode to '54g Auto' for the widest compatibility. Select the
mode to '54g Performance' for the fastest performance with 54g certifi ed
equipment. Set the mode to '54g LRS' if you are experiencing diffi culty
communicating with legacy 802.11b equipment.
In 'Auto' mode the NB9W will use RTS/CTS to improve 802.11g
performance in mixed 802.11g/802.11b networks. Turn protection 'Off' to
maximize 802.11g throughput under most conditions.
WMM stands for Wi-Fi Multimedia, that provides features that improve
the user experience for audio, video and voice applications over a Wi-Fi
networks.
TM will communicate at the maximum rate sustainable for each class of device, and also provide
TM
-compatible network devices allowing a total theoretical bandwidth of 108Mbps.
TM
-equipped wireless network client machines, enable Xpress
TM Technology 1
TM
; otherwise, don't enable.
NB9/NB9W ADSL2+ VoIP Router
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