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Chapter 5: Configuring the Wireless-G Broadband Router
The Wireless Tab - Advanced Wireless Settings
Wireless-G Broadband Router with SRX400
The Wireless Tab - Advanced Wireless Settings
This tab is used to set up the Router’s advanced wireless functions. These settings should only be adjusted by an
expert administrator as incorrect settings can reduce wireless performance.
Advanced Wireless
Basic Rate Set. The Basic Rate is not the actual rate of data transmission; it is a series of rates at which the
Router can transmit. (If you want to specify the Router’s rate of data transmission, configure the Transmission
Rate setting.) The Router will advertise its Basic Rate Set to the other wireless devices in your network, so they
know which rates will be supported. The Router will also advertise that it will automatically select the best rate
for transmission. In most cases, you should keep the default setting, Basic Rate Set #2, which includes higher
data rates for higher performance. If your wireless computers or other clients cannot associate with the Router,
select Basic Rate Set #1, a set of data rates specified by the 802.11b standard.
Transmission Rate. The rate of data transmission should be set depending on the speed of your wireless
network. You can select from a range of transmission speeds, or you can select Auto to have the Router
automatically use the fastest possible data rate and enable the Auto-Fallback feature. Auto-Fallback will
negotiate the best possible connection speed between the Router and a wireless client. The default value is Auto.
CTS Protection Mode. CTS (Clear-To-Send) Protection Mode should remain set to its default, Auto, so when your
Wireless-G products are not able to transmit to the Router in an environment with heavy 802.11b traffic, the CTS
Protection Mode will be used. This function boosts the Router’s ability to catch all Wireless-G transmissions but
will severely decrease performance.
Beacon Interval. The default value is 100. Enter a value between 1 and 65,535 milliseconds. The Beacon Interval
value indicates the frequency interval of the beacon. A beacon is a packet broadcast by the Router to synchronize
the wireless network.
DTIM Interval. This value, between 1 and 255, indicates the interval of the Delivery Traffic Indication Message
(DTIM). A DTIM field is a countdown field informing clients of the next window for listening to broadcast and
multicast messages. When the Router has buffered broadcast or multicast messages for associated clients, it
sends the next DTIM with a DTIM Interval value. Its clients hear the beacons and awaken to receive the broadcast
and multicast messages. The default value is 1.
Fragmentation Threshold. This value specifies the maximum size for a packet before data is fragmented into
multiple packets. If you experience a high packet error rate, you may slightly increase the Fragmentation
Threshold. Setting the Fragmentation Threshold too low may result in poor network performance. Only minor
reduction of the default value is recommended. In most cases, it should remain at its default value of 2346.
Figure 5-23: Wireless Tab - Advanced Wireless Settings
fragmentation: breaking a packet into smaller units
when transmitting over a network medium that
cannot support the original size of the packet.
cts (clear to send): a signal sent by a wireless
device, signifying that it is ready to receive data
beacon interval: data transmitted on your wireless
network that keeps the network synchronized
dtim: a message included in data packets
that can increase wireless efficiency.