Dell PowerConnect W Airwave 7.1, Руководство пользователя

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Dell PowerConnect W AirWave 7.1 | User Guide Configuring and Using Device Groups in AWMS | 101
3. Locate the Radio Settings area and adjust these settings as required. Table 61 describes the settings and
default values.
Table 61 Groups > Radio Fields and Default Values
Setting Default Description
Allow Automatic Channel Select (2.4,
5 GHz and 4.9GHz)
No If enabled, whenever the AP is rebooted it uses its radio to scan the
airspace and automatically select its optimal RF channel based on
observed signal strength from other radios.
NOTE: If you enable this feature, AWMS automatically reboots the APs in
the group when the change is implemented.
802.11b Data Rates (Mb/sec) 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, Aruba recommends leaving 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, Aruba recommends
leaving 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.
Beacon Period (19-5000 K μ sec) 100 Time between beacons (in kilo 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.