Somewhat of a general question about QoS and WiFi.
I use wAP ac in my test setup, where I transfer data (no internet connection presen, it is not needed) from a linux desktop to a laptop. Desktop is connected via ethernet to Mikrotik. Laptop is conencted to wAP’s wlan1 (2.4GHz) interface.
My goal is to prioritize specific TCP flow and always guarantee a specific amount of bandwidth for it with lowest possible delay. I allow starvation of other streams, so “fairness” is not the goal.
I have been experimenting with a lot of configurations of Queue Trees, Simple Queues, different types of underlying queues and so on.
Generally my problem is that all of them require the traffic to saturate the link completely in order to start scheduling, policing, shaping, etc. This also implies that a specific “max-limit” for my connection is set. However, due to high signal strength and bandwidth variations (in my use case) I can not estimate the max-limit. This throws all configs of Queue Trees and Simple Queues out of the window.
The only thing left is WMM (WiFi multimedia), which works semi-acceptable in my case. However, I wonder, if there is any way to configure Queue Trees or Simple Queues so that they are able to work with highly variable available physical bandwidth (highly variable “max-limit”)?
I use DSCP values (set on the sender side). Packet priorities are then set with help of mangle rules and DSCP values. Does AMPDU bring some extra benefit or is it just another method of marking packets?
Does AMPDU bring some extra benefit or is it just another method of marking packets?
A-MPDU is a major factor in wifi performance with large volumes, and will reduce the 802.11 overhead dramatically.
In MT it is only enabled for priority 0, which is all traffic if priority is not set by FW rules. It should be on for all priorities, unless there is a reason to leave it off.
Leaving it off for priority 6 and 7 can be justified because voice is normally low throughput, but very sensitive to response-time (no buffering allowed).
But if you want priority and throughput, I would put it on.