[SOLVED] Two Mesh Network Questions

Crag_Hack

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Hi I have a couple mesh network questions.

1. I've set up a bunch of mesh networks specifically Google Nest Wifi's and Netgear Orbi RBK50's. For some reason the speed usually degrades significantly at the far reaches of the network (not that far... maybe 25-30 feet max from the satellite). I get ~50 Mbps max maybe. If the mesh wifi device advertises 1.2 Gbps for the satellite (for the nest wifi) how come it drops off so rapidly? We're talking two spatial streams for 833 Mbps on the 5 GHz ac band right? Is it because the device receiving data say the smartphone only has one spatial stream and therefore the theoretical max is 433?

2. Does anybody have any experience with mesh network extenders like these? They're dramatically less expensive than buying a whole 2-3 device mesh network system. Are they reliable and perform well or not so good?

Thanks!
 
Solution
The first thing you have to realize is mesh is all marketing speak. There is no magic it is just a slightly better repeater but with many of the same issues.

This is on top of the fake number they already put on wifi boxes.

So if we look at the more simple case of just a router and a single end device and assume some average distance from the router. You might get 300mbps real life speed from these and that is even if you use fancy 4x4 mimo.

Now you add in repeaters. The cheapest repeater will cut your speed by at least 1/2 of that. First and most important wifi is half duplex so only 1 device can transmit at time. Any interference to the signal is amplified because you have multiple chances to get retransmission.

The...
The first thing you have to realize is mesh is all marketing speak. There is no magic it is just a slightly better repeater but with many of the same issues.

This is on top of the fake number they already put on wifi boxes.

So if we look at the more simple case of just a router and a single end device and assume some average distance from the router. You might get 300mbps real life speed from these and that is even if you use fancy 4x4 mimo.

Now you add in repeaters. The cheapest repeater will cut your speed by at least 1/2 of that. First and most important wifi is half duplex so only 1 device can transmit at time. Any interference to the signal is amplified because you have multiple chances to get retransmission.

The better mesh systems try to reduce this by using extra radio chips to talk back to the main router to reduce the conflict between the signals. Problem is there is very limited bandwidth on the 5g band. Doing this pretty much uses all the 5g bandwidth which guarantees you conflict with neighbors wifi signals.

Now if you are trying something like router---mesh---mesh---end device. That is also going to greatly reduce your speed even more because you have have 3 radio links.

Some key problems wifi6. To get the fast speeds it must run 160mhz radio bands and it must use qam1024. Qam1024 only works well close to the router and any repeater would almost have to be placed in the same room. Next many wifi 6 device only support 80mhz channels. This is because of all the weather radar avoidance rules.
So without these 2 key feature wifi6 will pretty much run the same as a 802.11ac. This is why you see so many people say wifi6 is not faster for them.

It is almost impossible to run a repeater using wifi6. There just is not enough bandwidth to run 2 160mhz signals and it makes the radar avoidance stuff even more difficult. Maybe wifi6e stuff that can run on the 6g radio band might work but this stuff is just starting to come onto the market so I don't know if there is a mesh system.


In the end you should only use mesh/repeater systems when you have no other options. You just accept that a crappy repeated signal is better than no signal from the main router. You need to consider Moca or powerline networks to get the signal to the remote parts of the house and attach AP to provide the wifi signals.
 
Solution

Crag_Hack

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@bill001g Thanks for the awesome reply.

I guess mesh networks suffice for most people whose needs max out at ~25 Mbps for 4k streaming. Which is all of my clients I've done these for.

When you say 300 Mbps with 4x4 MIMO does that mean 4 antennas on both ends? Is that the equivalent of 4 spatial streams? Will a device with 1 antenna get the kind of results I'm seeing where it maxes out at ~50 or so? Do most common budget laptops and average smartphones only have 1 antenna or spatial stream?

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Also does anybody know if the mesh extenders here are any good? Are they inferior or equal to a whole mesh system?
 
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That is what 4x4 mimo means. Going from 1x1 to 2x2 gives a large increase (not even close to double). Adding more antenna gives less and less additional which is why we don't see 100x100. It took them very many years to get 4x4 to work acceptably.

Most modern devices have 2 antenna. This is the number you see on the box called 1200 and it gives 866 data encoding rate on the 5g radio. It is not uncommon for people to see more than 200mbps using 2x2 and even more than 100mbps using 1x1.

In your case your problems maybe because you are using the 2.4g radio band. This is limited to 40mhz channels so you start with data 1x1 encoding rates of only 150. You will not even get 1/2 of that because wifi is half duplex and there is lots of other overhead. It is very common for people to get in the 50mbps range on a 1x1 2.4g connection.

2.4g has much better ability to go though walls etc so it tends to have better coverage than 5g.

The key to using any mesh/repeater system is placement of the devices. You have many people who are too lazy to read any instructions and think they can just place these devices in the remote rooms. They must be placed in a location that they can get good signal from the main router but still transmit a strong signal to the remote room. Many times this location does not exist, or it would require putting it inside the wall or ceiling with a antenna on both sides. People with say concrete walls have no solution because wifi is absorbed so well by concrete but many things can stop it even paint that has metal in it.

Again your solution to coverage issues is to find a way to get some kind of "wire" between the router and the remote rooms.
 

Crag_Hack

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@bill001g Thanks again :) Do you think these mesh systems are defaulting to 2.4 GHz when travelling through a wall or two and having the device ~20+ or so feet away from the nearest satellite? Is there any other factor that could be causing the sub-100 speeds? Also interesting how I read PCWorld and Tom's Hardware etc and nobody ever mentioned these things. All I've ever heard is praise for mesh networks but my experience definitely tells me they aren't so magical like you've been saying.

Also if you go here it shows my S10+ has 4x4 MIMO and should max out at 2 or 1.2 Gbps download (not sure which is correct) but I still get slow speeds on my phone with mesh networks when I'm not close to the router or satellite. Same reason as above maybe? I just looked my Oookla Speedtest history of results and 95% are sub-100. All of these tests were performed to test mesh network capacity.
 
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First many of the articles are actually paid advertisements. Next most people writing these article generally have degrees in journalism or maybe no degree at all. These people pretty much just parrot marketing garbage they get from the company making the product. You seldom see stuff written by someone who has say a electrical engineering degree or any really strong technical background. The pay is much better actually designing stuff than getting paid to write articles.

There is no standard for mesh every company makes up their own rules. In theory the best mesh systems will have a dedicated 5g radio between the router and the mesh system. It will then have another pair of radio chips to talk to the end users one on 2.4 and another on 5. You should be able to tell if your device is connecting to 5g or 2.4. You should be able to force it via SSID if nothing else. Most mesh systems do not have these dedicated radio chips because it greatly increases the price.

I am very surprised a phone has 4x4 mimo. What you would have to next do it find the FCC ip number and look at the reports they must file. There should be a document that tell the output power when they are running 4x4 mimo. Most routers are near the legal maximum end devices like phones may not be because it eats more battery to transmit at high power.

In general even using 4x4 mimo you will not get over 350-400mbps. To get higher you must run wifi6 with both qam1024 and 160mhz channels. Those get in the 600mbps range. Still far short of their 3gbit or whatever they claim.

I would turn off all the repeaters so they are not interfering. Then go stand by your main router and see what the best case condition you can get.
 

Oasis Curator

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Don't always think mesh network is garbage though.
It may be a fancy name but "poached eggs" is also a fancy name for eggs.

I had home plugs, which gave me around 5MB-10MB.
Changed to a mesh network and now I get closer to 100MB.

While I've switched from wired to wireless, I wouldn't have done that without all the "garbage" marketing of mesh networks and how they work.
 
Moca and powerline networks are actually very simple devices they have little to no concept of wifi or ip addresses they are pass data looking only at mac addresses.

For most people they take the place of a ethernet cable. Not sure why you would ever need a mesh network if you cable all your wifi radios.

Now most mesh systems will support ethernet but this is nothing new. The design of using AP connected to a central location via ethernet has been used by enterprise installs since the very first wifi network came out 20yrs ago. The mesh guys just want to pretend this is something new so they can sell you expensive boxes. Any router can be used as a AP rather than pay extra for mesh. You only use mesh where you can't cable it.

You can set the SSID on AP or routers the same or different, up to you. Although mesh units try to claim roaming this is mostly a lie. The end device not the network is in control of what it connects to. Wifi was never really designed for roaming unlike cell towers where the tower has full control of the radio in your phone.

The problem you have when the SSID is the same is the end device might stay connected to a lower power signal rather than switch. Mostly this is poor wifi layout design rather than software. You need to adjust the radio power to have as little overlap as possible. In general a correctly designed wifi network will allow the device to switch by the time you move room to room. This has nothing to do with mesh, it is all about adjusting the radio power on the remote units. Now if you think you can play your game or watch netflicks while you walk down your stairs to another room you need to rethink if this is really a smart thing to do even if the technology could do it.

For many people that do not want to mess with measuring radio power on devices and setting levels it is easier to just use different SSID. That way the human can decide what is the best to connect to for all the different conditions. People are not constantly running around their house so changing the SSID manually can be a better option for some.
 
You almost can't compare the technology. The very newest models of moca have 2.5g ports on them. Not sure how fast you can really get but the slightly older units that use the same transmission method but only had gigabit port could actually get 900+mbps, about the same as a ethernet cable. powerline units you will not get much over 300mbps if you are very lucky.

I don't know for sure the limits on rg59. I know you can run more distance on rg6 but many people report rg59 work fine for moca.