Allen-Bradley 1783-WAPAK9, Руководство пользователя

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538 Rockwell Automation Publication 1783-UM006A-EN-P - May 2014
Chapter 20 Configuring Repeater and Standby Access Points and Workgroup Bridge Mode
Configuring a Workgroup
Bridge for Roaming If your workgroup bridge is mobile, you can configure it to scan for a better radio
connection to a parent access point or bridge. Use this command to configure the
workgroup bridge as a mobile station:
ap(config)# mobile station
When you enable this setting, the workgroup bridge scans for a new parent
association when it encounters a poor Received Signal Strength Indicator (RSSI),
excessive radio interference, or a high frame-loss percentage. By using these
criteria, a workgroup bridge configured as a mobile station searches for a new
parent association and roams to a new parent before it loses its current
association. When the mobile station setting is disabled (the default setting) the
workgroup bridge does not search for a new association until it loses its current
association.
Configuring a Workgroup
Bridge for Limited Channel
Scanning In mobile environments such as railroads, a workgroup bridge instead of scanning
all the channels is restricted to scan only a set of limited channels to reduce the
hand-off delay when the workgroup bridge roams from one access point to
another. By limiting the number of channels the workgroup bridge scans only to
those required, the mobile workgroup bridge achieves and maintains a
continuous wireless LAN connection with fast and smooth roaming.
Configuring the Limited Channel Set
This limited channel set is configured by using the mobile station scan
<set of
channels>
command to invoke scanning to all or specified channels. There is
no limitation on the maximum number of channels that can be configured. The
maximum number of channels that can be configured is restricted only by the
number of channels a radio can support. When executed, the workgroup bridge
scans only this limited channel set. This limited channel feature also affects the
known channel list that the workgroup bridge receives from the associated access
point. Channels are added only to the known channel list if they are also a part of
the limited channel set.
The following example shows how the command is used. In the example,
channels 1, 6, and 11 are specified to scan:
ap#
ap#confure terminal
Enter configuration commands, one per line. End
with CNTL/Z.
ap(config)#int d0
ap(config-if)#ssid limited_scan
ap(config-if)#station-role workgroup-bridge
ap(config-if)#mobile station
ap(config-if)#mobile station scan 1 6 11