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Is it possible to configure a Cisco 851W wireless router to only use 802.11g (as opposed to 802.11b)?

If so, could someone tell me what configuration changes are necessary?

Current wireless configuration:

interface Dot11Radio0
 no ip address
 encryption vlan 1 mode ciphers tkip 
 encryption mode ciphers tkip 
 ssid MYSSID
 speed basic-1.0 basic-2.0 basic-5.5 basic-6.0 basic-9.0 basic-11.0 basic-12.0 basic-18.0 basic-24.0 basic-36.0 basic-48.0 basic-54.0
 channel 2462
 station-role root
 no cdp enable
interface Dot11Radio0.1
 encapsulation dot1Q 1 native
 no cdp enable
 bridge-group 1
 bridge-group 1 subscriber-loop-control
 bridge-group 1 spanning-disabled
 bridge-group 1 block-unknown-source
 no bridge-group 1 source-learning
 no bridge-group 1 unicast-flooding
share|improve this question
up vote 1 down vote accepted

You need to disable the 802.11b speeds like this:

interface dot11radio 0
#getting rid of b speeds
no speed basic-1.0 basic-2.0 basic-5.5
#Adding the g speeds here
speed basic-12.0, basic-18.0, basic-24.0, basic-36.0, basic-48.0, and basic-54.0

You may also want to enable speed slotting once you are running only 11g, it is a radio interface subcommand:

share|improve this answer
Thanks! That answered it! If anyone else is interested, the 802.11g speeds are: 6, 9, 12, 18, 24, 36, 48, and 54 So you would want the following interface command: speed basic-6.0 basic-9.0 basic-12.0 basic-18.0 basic-24.0 basic-36.0 basic-48.0 basic-54.0 – Avalanchis Oct 27 '09 at 14:13
Short slot time will give you even better 802.11g performance by changing the amount of back-off time from 20ms down to 9ms. Depending on your user count it can be a noticeable performance increase. – sparks Oct 27 '09 at 14:34

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