Configuring Dynamic Frequency Selection On An Access Point - Cisco 800 series Configuring

How to Configure Radio Settings on an Access Point

Configuring Dynamic Frequency Selection on an Access Point

Perform this task to configure DFS on an access point with a 5-GHz radio.
Dynamic Frequency Selection on Access Points with 5-GHz Radios
This section applies only to wireless access points shipped to Europe and Japan with 5-GHz radios
running Cisco IOS version 12.4(6)T. Access points shipped to Europe and Japan with 5-GHz radios are
required to use DFS to detect and avoid interfering with radar signals to comply with that regulatory
domain.
The access point automatically sets the operating frequency on a DFS-enabled 5-GHz radio. A specific
channel cannot be configured for DFS-enabled 5-GHz radios; the channel command is disabled.
If the access point is set to use DFS and it is deployed in a regulatory domain that does not allow or does
Note
not require the use of DFS, disable DFS by using the no dfs band block interface configuration
command.
DFS-enabled 5-GHz radios monitor the operating frequency for radar signals. If radar signals are
detected on the channel, the access point takes these steps:
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When a DFS-enabled 5-GHz radio operates on one of the following 15 channels, the access point
automatically uses DFS to set the operating frequency:
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10
Blocks new transmissions on the channel.
Flushes the power-save client queues.
Broadcasts an 802.11h channel-switch announcement.
Disassociates remaining client devices.
Randomly selects a different channel:
If the access point does not select a DFS-required channel, the access point enables beacons and
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accepts client associations.
If the access point selects a DFS required channel, the access point scans the new channel for
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radar signals for 60 seconds. If there are no radar signals on the new channel, the access point
enables beacons and accepts client associations. If a radar signal is detected, the access point
selects a different channel.
52 (5260 MHz)
56 (5280 MHz)
60 (5300 MHz)
64 (5320 MHz)
100 (5500 MHz)
104 (5520 MHz)
108 (5540 MHz)
112 (5560 MHz)
116 (5580 MHz)
120 (5600 MHz)
124 (5620 MHz)
Configuring Radio Settings on an Access Point