When capping the downlink modulation and uplink modulation to SS modes like SS MCS 4 the radios downlink and uplink modulation goes past SS MCS 9 and goes as high as DS MCS 4. Why does this happen?
I am trying to reduce retransmissions , capacity drop packets as much as possible since i’m on a 15 mbps plan
I’m curious why you would want to specify a Single Stream modulation?
Also - if you’re on a 15Mbit plan, and if you reduce your modulation to much, you’ll start to occupy a higher and higher percentage of the AP’s air time total. For example, on narrow channel width and 802.11n/ac, MCS4 SS has a signaling rate around 40 megabit, so (just ball parking here) pulling 15 Mbps at that low SS modulation, might be using 50%-75% of the AP’s airtime capacity… so (just a spitball ballpark calculation)
I was about to ask everything that @ninedd just said… and add that it’s typically not a good idea to limit or rate lock the modulation in order to deliver a specific service tier. You’ll want to use something at the head end, like Cambium QoE to provide shaping/rate limiting… OR just use the radio’s built in QoS rate limiter to set the SM’s MIR to 15mbps.
AC 80MHz
because retransmissions are affecting online gaming jitter
I don’t have access to the AP
It’s controlled by my ISP
I want to limit even further to to see how much of the retransmissions I can get it down to.
at DS MCS 9 retransmission were hovering at 15% after 24hours
Now when limited to DS MCS 1 its hovering at 3% after 24 hours and jitter has really improved in the games I play but its still there partly
The best way to resolve this issue is by having the ISP change the channel, channel width, or even the TDD type (flexible or fixed). I would only change the MCS rate as a last resort and I would not allow the customer to control this.
On the AP side MCS rates can be configured to allow for either dual stream (DS) or single stream (SS) rates… but this is for all the clients connected to the AP, and as I mentioned above, I would never do this for a single customer as it would impact all the customers and the overall AP performance.
Tried talking to my ISP to change channel or atleast an alternate 40 or 20mhz channel on the access point and they don’t want to solve my issue of low link quality and retransmissions. decided to just limit mcs instead! im using a force 300-25l and it has ss and ds mcs
Then you’re stuck… there’s nothing else you can do… except maybe find a new ISP.
