Wireless data rates

[carl_townshend]

Hi All

I know that with 802.11a/b/g you see wireless data rates advertised in the beacons etc, these normally go up to 54Mbit

Are these data rates negotiated by the ap and client depending on the rssi ?

Also, what about 802.11n and 802.11ac etc, what data rates get advertised with this?

[patoberli]

Check this: https://www.engeniustech.com/wi-fi-beacon-frames-simplified/
With the higher speeds it's a combination of MCS, spacial streams, ... which in the end define the actual speed.