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Wi is Fi: Understanding Wi-Fi 4/5/6/6E/7/8 (802.11 n/AC/ax/be/bn)

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Re: Wi is Fi: Understanding Wi-Fi 4/5/6/6E/7/8 (802.11 n/AC/ax/be/bn)

#3

Post by Havoc »

Nice detailed article!

Finding it increasingly difficult to avoid bottlenecks though. Even with wifi 7 I still get 1.3 on my mac and 0.5 on iphone. More than enough realistically, but upstream internet is 1.7 so tiny bit unfortunately

Think I'm just going to wire the place with 10 gig fiber

>The speed advantages that Access Points have over mesh systems will become much more obvious with Wi-Fi 7.

From what I've read mesh devices generally can detect when they've got wired backhaul so they can stay in mesh mode for the clean handovers while not relying on it for actually moving data

Re: Wi is Fi: Understanding Wi-Fi 4/5/6/6E/7/8 (802.11 n/AC/ax/be/bn)

#4

Post by KingMachiavelli »

I'd like to understand why the WiFi spec developed so slowly from G to N and finally to AC but now it's seems like a new version is released every other year yet many of the features/extensions are poorly implemented or have nearly 0 real world improvement.

Re: Wi is Fi: Understanding Wi-Fi 4/5/6/6E/7/8 (802.11 n/AC/ax/be/bn)

#5

Post by anyfoo »

Havoc wrote: post #3

Nice detailed article! Finding it increasingly difficult to avoid bottlenecks though. Even with wifi 7 I still get 1.3 on my mac and 0.5 on iphone. More than enough realistically, but upstream internet is 1.7 so tiny bit unfortunately Think I'm just going to wire the place with 10 gig fiber >The speed advantages that Access Points have over mesh systems will become much more obvious with Wi-Fi 7. From what I've read…

Due to boring circumstances outside of my control, I have to use WiFi for the most part, so I've got quite some experience with making it run optimally (or rather, as optimally as I managed to, not as optimally as I would like it to).

And yeah, you pretty much already have to have a visible line of sight to get anything even close to 1 Gbps. And still be on channels with little interference. (DFS helps if you're not near radar, which intentionally causes you to get kicked off those channels and lose connection entirely.) And even then you might have to mess about a lot with positioning, because of reflections and generally multipath propagation.

I'd say it's not worth the headache. I would love to lay down Ethernet cable, even if it was just cabling only suitable for 1 Gbps (for which there's no good reason to, might as well do 10 Gbps).

But yeah, any mesh system worth its salt figures out the topology and absolutely favors wired links over WiFi for the back haul. Anything else wouldn't make any sense at all, there is basically no situation where you'd prefer an RF channel over a wire, unless the wire is maybe made of wet string.

Re: Wi is Fi: Understanding Wi-Fi 4/5/6/6E/7/8 (802.11 n/AC/ax/be/bn)

#6

Post by crims0n »

KingMachiavelli wrote: post #4

I'd like to understand why the WiFi spec developed so slowly from G to N and finally to AC but now it's seems like a new version is released every other year yet many of the features/extensions are poorly implemented or have nearly 0 real world improvement.

Surely some of that was need. When G was dominant from around 2004-2009 the theoretical maximum was 54mbps… most people were still on DSL or cable at the time, often capping out way below that.

Re: Wi is Fi: Understanding Wi-Fi 4/5/6/6E/7/8 (802.11 n/AC/ax/be/bn)

#7

Post by walrus01 »

Havoc wrote: post #3

Nice detailed article! Finding it increasingly difficult to avoid bottlenecks though. Even with wifi 7 I still get 1.3 on my mac and 0.5 on iphone. More than enough realistically, but upstream internet is 1.7 so tiny bit unfortunately Think I'm just going to wire the place with 10 gig fiber >The speed advantages that Access Points have over mesh systems will become much more obvious with Wi-Fi 7. From what I've read…

how many spatial streams are you using (2x2, 3x3, etc) and are you using an 80 or 160 MHz channel?

If you have a set of full capability 802.11be clients you'll see the best performance with a 3x3 AP and 160 MHz channels.

Re: Wi is Fi: Understanding Wi-Fi 4/5/6/6E/7/8 (802.11 n/AC/ax/be/bn)

#9

Post by walrus01 »

anyfoo wrote: post #5
Havoc wrote: post #3

Nice detailed article! Finding it increasingly difficult to avoid bottlenecks though. Even with wifi 7 I still get 1.3 on my mac and 0.5 on iphone. More than enough realistically, but upstream internet is 1.7 so tiny bit unfortunately Think I'm just going to wire the place with 10 gig fiber >The speed advantages that Access Points have over mesh systems will become much more obvious with Wi-Fi 7. From what I've read…

Due to boring circumstances outside of my control, I have to use WiFi for the most part, so I've got quite some experience with making it run optimally (or rather, as optimally as I managed to, not as optimally as I would like it to). And yeah, you pretty much already have to have a visible line of sight to get anything even close to 1 Gbps. And still be on channels with little interference. (DFS helps if you're not…

> And yeah, you pretty much already have to have a visible line of sight to get anything even close to 1 Gbps

If one considers that the higher speeds in 802.11ac and 802.11be require 256QAM modulation or better, this is completely expected (assuming 5 GHz band of course, which doesn't go through material very well at all). If you've sen a live eyeball chart of a 256QAM or 1024QAM constellation on test equipment for clear-air microwave link purposes, and seen how quickly it can degrade or get fuzzy if there's anything in the way of the link, it becomes more readily apparent. MCS levels 8 and onwards here:

https://en.wikipedia.org/wiki/Wi-Fi_7

"Clean" eyeball example of 256QAM: https://www.everythingrf.com/community/what-is-256-qam-modul...

examples of "fuzzy qam" in 16QAM, same principle applies to denser QAM

https://www.researchgate.net/figure/Typical-eye-diagram-Symb...

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