Re: [Codel] [Cake] [Make-wifi-fast] [Starlink] [Cerowrt-devel] Due Aug 2: Internet Quality workshop CFP for the internet architecture board

[Ben Greear <greearb@candelatech.com>]

On 8/2/21 4:16 PM, David Lang wrote:
> If you are going to setup a test environment for wifi, you need to include the ability to make a fe cases that only happen with RF, not with wired networks and 
> are commonly overlooked
> 
> 1. station A can hear station B and C but they cannot hear each other
> 2. station A can hear station B but station B cannot hear station A 3. station A can hear that station B is transmitting, but not with a strong enough signal to 
> decode the signal (yes in theory you can work around interference, but in practice interference is still a real thing)
> 
> David Lang
> 

To add to this, I think you need lots of different station devices, different capabilities (/n, /ac, /ax, etc)
different numbers of spatial streams, and different distances from the AP.  From download queueing perspective, changing
the capabilities may be sufficient while keeping all stations at same distance.  This assumes you are not
actually testing the wifi rate-ctrl alg. itself, so different throughput levels for different stations would be enough.

So, a good station emulator setup (and/or pile of real stations) and a few RF chambers and
programmable attenuators and you can test that setup...

 From upload perspective, I guess same setup would do the job.  Queuing/fairness might depend a bit more on the
station devices, emulated or otherwise, but I guess a clever AP could enforce fairness in upstream direction
too by implementing per-sta queues.

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com