Users Guide

Dell PowerConnect W-AirWave | User Guide Configuring and Using Device Groups in AMP | 87
3. Locate the Radio Settings area and adjust these settings as required. Table 60 describes the settings and
default values.
4. Certain wireless access points offer proprietary settings or advanced functionality that differ from prevailing
industry standards. If you use these APs in the device group, you may wish to take advantage of this
proprietary functionality.
Table 60 Groups > Radio > Radio Settings Fields and Default Values
Setting Default Description
Allow Automatic Channel
Selection (2.4, 5, and
4.9GHz Public Safety)
No If enabled, whenever the AP is rebooted it uses its radio to scan the airspace and
select its optimal RF channel based on observed signal strength from other radios.
NOTE: If you enable this feature, AMP automatically reboots the APs in the group
when the change is implemented.
802.11b Data Rates
(Mbps)
Required:
 1.0
 2.0
Optional:
 5.5
 11.0
Displays pull-down menus for various data rates for transmitting data.
NOTE: This setting does not apply to Cisco LWAPP devices.
The three values in each of the pull-down menus are as follows:
 Required—The AP transmits only unicast packets at the specified data rate;
multicast packets are sent at a higher data rate set to optional. (Corresponds to a
setting of yes on Cisco devices.)
 Optional—The AP transmits both unicast and multicast at the specified data
rate. (Corresponds to a setting of basic on Cisco devices.)
 Not Used—The AP does not transmit data at the specified data rate.
(Corresponds to a setting of no on Cisco devices.)
Frag Threshold Enabled No If enabled, this setting enables packets to be sent as several pieces instead of as one
block. In most cases, leave this option disabled.
Threshold Value 2337 If Fragmentation Threshold is enabled, this specifies the size (in bytes) at which
packets are fragmented. A lower Fragmentation Threshold
setting might be required
if there is a great deal of radio interference.
RTS/CTS Threshold
Enabled
No If enabled, this setting configures the AP to issue a RTS (Request to Send) before
sending a packet. In most cases, leave this option disabled.
RTS/CTS Threshold Value 2338 If RTS/CTS is enabled, this specifies the size of the packet (in bytes) at which the AP
sends the RTS before sending the packet.
RTS/CTS Maximum
Retries
32 If RTS/CTS is enabled, this specifies the maximum number of times the AP issues an
RTS before stopping the attempt to send the packet through the radio.
Acceptable values range from 1
to 128.
Maximum Data Retries 32 The maximum number of attempts the AP makes to send a packet before giving up
and dropping the packet. Acceptable values range from 1 to 255.
Beacon Period (19-5000
msec)
100 Time between beacons (in microseconds).
DTIM Period (1-255) 2 DTIM alerts power-save devices that a packet is waiting for them. This setting
configures DTIM packet frequency as a multiple of the number of beacon packets.
The DTIM Interval indicates how many beacons equal one cycle.
Ethernet Encapsulation RFC1042 This setting selects either the RFC1042 or 802.1h Ethernet encapsulation standard for
use by the group.
Radio Preamble Long This setting determines whether the APs uses a short or long preamble. The
preamble is generated by the AP and attached to the packet prior to transmission.
The short preamble is 50 percent shorter than the long preamble and thus may
improve wireless network performance.
NOTE: Because older WLAN hardware may not support the "short" preamble, the
"long" preamble is recommended as a default setting in most environments.