802.11ac has introduced 2 new MCS rates called MCS 8 & 9. By default 11ac APs use upto MCS 9 in all spatial streams.
But it can be configured to ensure that higher MCS rates are not used.
MCS 8 and 9 introduces 256 QAM with Convolution coding of 3/4 and 5/6 rates respectively. These rates are supported in all the Spatial streams. AP 225 supports a maximum of 3 spatial streams.
Environment : AOS version: 22.214.171.124 AP: AP 225
Network : Controller --------- AP 225s )) (( 11ac Clients.
The configuration to specify the required MCS rates for specific SSID can be done in "WLAN HT-SSID profile". By default max MCS is 9 for all Spatial streams. This can be reduced in Ht ssid profile as below.
Add or revome necessary MCS rates in the HT-ssid profile and map it to the corresponding ssid profile.
To validate if the configuration has taken effect, check the below command: