Enabling 802.11b only WiFi

I a using a 802.11bgnac supported radio. Is there a possibility to set 802.11b ONLY from LuCI interface.

Below are the values that will be set in the wireless config for different options.

option hwmode '11g' is set for legacy 2.4GHZ
option hwmode '11a' is set for legacy 5GHz
option hwmode '11g' is set when 802.11n is selected
option hwmode '11a' is set for 802.11ac

Setting the legacy rates and selecting 2.4GHZ sets the value as '11g' which is an indication of both b/g.
Disabling Legacy rates would make it to operate only in '11g' mode.

Would want to set the option form LuCI to allow device to set only to 802.11b mode to operate at 2.4GHZ and use DSSS only.

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hwmode string no (driver default) Selects the wireless protocol to use, possible values are 11b , 11g , and 11a . Note that 11ng and 11na are not available options

im looking into the same thing for a long distance link. the command line\config files can be set with hwmode 11b i suppose.

no luci, just command line or config file

Do not expect that modern hardware can do a really standards compliant 802.11b signal, enough to get your connected (but I doubt anyone has tested this mode in years (at all, on n, ac or ax hardware), so you can expect bugs), but not good enough to validate 802.11b functionality of other devices.

Given that 802.11b uses a 22 MHz carrier, I'd strongly recommend against using this mode lightly, you're messing up the ether for your neighbours and hurt both your own and their throughput.


i bet the vast majority of my neighbours would not know wtf i am talking about if i told them their wifi uses 40mhz width on the 2.4ghz band (they do).

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B and G are essentially the same thing once you remove all symbol rates higher than 11mbps. I believe there is a spot in the config you can uncheck speeds (I might be dreaming, but I know it exists on Cisco AP's).

I can check it later when I have access to my web interface.

EDIT:Speed wise I guess, I forgot about the whole OFDM thing. It's been ages since I needed this information.

I hope you're only doing this on a point-to-point link, as using 802.11b-only causes interference with modern 802.11 configurations.


Also, it's not legal to knowingly configure your radio to cause interference to others.

I think this is the legal setting on devices manufactured after IEEE 802.11-1999 was accepted anyways. This is a very similar to the situation with older devices/chips that expose the "Force 40MHz mode" setting (which would violate IEEE 802.11n-2009 today if added to new devices - a setting commonly added to modern devices improperly by OEMs for a "performance only mode" button or similar).

Basically, the device should attempt to use modes/etc. that increase available bandwidth and cause the least interference.

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If in the US, Part 15 devices are not permitted cause "harmful" interference to other devices. This might exclude other Part 15 devices, but if you run B and some licensed WISP complains, you would be required to modify your setup to halt the interference.

I still don't think we've been given a proper response as to why B mode is required rather than limiting the data rate in another more compliant way.

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