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Chapter 5: Configuring the Wireless-G Cable Gateway
The Wireless Tab
Wireless-G Cable Gateway
Advanced Wireless Settings Tab
On this screen you can access the Advanced Wireless features, including Basic Data Rates, Control Tx Rates,
Beacon Interval, DTIM Interval, Fragmentation Threshold, RTS Threshold, and Authentication Type.
•
Basic Data Rates. Select
Min
or
All
from the drop-down menu for rate.
•
Control Tx Rates. Select
Min
or
All
from the drop-down menu for the transmission rate. All will negotiate the
best possible connection speed between the Gateway and a wireless client.
•
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 Gateway
to synchronize the wireless network.
•
DTIM Interval. The default value is
3
. This value, between 1 and 255 milliseconds, 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 Gateway 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.
•
Fragmentation Threshold.
This value should remain at its default setting of
2346
. The range is 256-2346
bytes. It 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 decrease the Fragmentation Threshold. Setting the
Fragmentation Threshold too low may result in poor network performance. Only minor modifications of this
value are recommended.
•
RTS Threshold.
This value should remain at its default setting of
2347
. The range is 0-2347 bytes. Should you
encounter inconsistent data flow, only minor modifications are recommended. If a network packet is smaller
than the preset RTS threshold size, the RTS/CTS mechanism will not be enabled. The Gateway sends Request
to Send (RTS) frames to a particular receiving station and negotiates the sending of a data frame. After
receiving an RTS, the wireless station responds with a Clear to Send (CTS) frame to acknowledge the right to
begin transmission.
•
Authentication Type. The default is set to Open System or Shared Key, which allows either Open System or
Shared Key authentication to be used. For Open System authentication, the sender and the recipient do NOT
use a WEP key for authentication. For Shared Key authentication, the sender and recipient use a WEP key for
authentication. If you want to use only Shared Key authentication, then select
Shared Key
. In most cases, you
should keep the default,
Open System or Shared Key
.
When finished making your changes on this tab, click the
Save Settings
button to save these changes, or click
the
Cancel Changes
button to undo your changes.
Figure 5-16: Advanced Wireless Settings
fragmentation:
breaking a packet into smaller units
when transmitting over a network.
dtim
(delivery traffic indication message): a message
included in data packets that can increase wireless
efficiency.
beacon internal:
data transmitted on your wireless network
that keeps the network synchronized.
packet:
a unit of data sent over a network.
rts
(request to send): a networking method of coordinating
large packets through the RTS Threshold setting.