How to disable MU-MIMO and/or Transmit Beamforming

[Hammer]

Is someone able to point me in the direction to disable MU-MIMO and/or Transmit Beamforming?

[PhilipDAth]

You can't disable them - and even if you could - it would be a terrible step backwards in time.  Those technologies greatly improve the reliability of WiFi.

[Hammer]

Actually, it does not greatly improve reliability. In fact, in almost all environments/implementations it has the opposite effect due to the overhead of the sounding that is involved.

I strongly recommend you invest the time to review Devin Akin's Webinar into ac wave 2. Here's a link - https://www.brighttalk.com/webcast/5522/252893/the-truth-about-802-11ac-wave-2-technology
At least review the MU-MIMO part starting 27:13 for about the next 10 minutes.

[mo_unify]

Thanks for sharing that @Hammer - Really interesting talk.

My biggest take away is the "pennies" analogy. So MU-MIMO does add value to a network, provided very, very specific conditions... but not enough to revolutionise RF.

I can't say I've experienced lots of noise/performance degradation from deploying MU-MIMO myself. What are some of the symptoms? 

[wonwif]

Just a thought, I've watched the Devin Akin's Webinar into ac wave 2 in the link and although it talks about very little benefit over using MU-MIMO, he does NOT explicitly state to "turn off" the MU-MIMO on the APs that are capable of this functionality?

Is this correct or did I miss something on the Webinar?

[Hammer]

Hi @wonwif

Thanks for actually taking the time to watch the webinar, I suspect a lot of people wouldn't bother. However, your take on what Devin says is very different to mine, I almost wonder if we where watching the same webinar.

Here are a few very negative quotes which pretty much say turn it off:

"...in some environments, if you turn on MU-MIMO, your environment completely dies right then..." (29:44)

"...almost no chance of giving you value but in a bad environment no chance what so ever..." (38:04)

Here he DOES explicitly state to "turn off" the MU-MIMO on the APs that are capable of this functionality.

"...the first thing I do all of my systems, that I implement, is turn off transmit beamforming and turn of MU-MIMO support. If the vendor's equipment supports that, I turn them off immediately. They are very high overhead and give no meaning value what so ever." (44:38)

Hope this helps.

[wonwif]

Hi Hammer,
Thanks for the reply and including the actual transcripts / quotes from the Webinar advising MU-MIMO to be turned off. I must admit I was kind of multitasking while watching(listening) to the webinar and my key takeaway from the Webinar was that the MU-MIMO has a very little performance gain as per the slide #17 of 24 “Focusing on MU is like picking up pennies when $100 bills are lying all around you” here http://public.brighttalk.com/resource/core/146591/wave2_netscout_269407.pdf

Overall, I would agree with turning off the MU-MIMO, if it did actually cause these system meltdown and I’m wondering if there is any data to show this info?

Once again thanks for sharing the webinar and responding to my post!
cheers

[mo_unify]

+1 agree with Philip,

In what application would you want to turn these technologies off?

It's like asking to turn off power steering in a car!