Wired backhaul and mesh

Installing and Using OpenWrt Network and Wireless Configuration
1

I got a 4pack of this one: https://www.amazon.co.uk/Zyxel-AX1800-System-Satellite-Compatible/dp/B0BCWF8FV2?th=1

my plan is to replace the stock router from a&a and have one of these act as router(with wifi), and the 3 others as AP's,

the thought so far is to have 2 on each floor even distributed so the connection is somewhat the same no matter where i'm

i would also like to have the same ssid and have the phones etc roam for the strongest one

there are wired connections but ideal i would like to have a mix of both wired backhaul and mesh (if its possible and dont come with drawbacks)

is that total nuts?

2

If you can wire them, forget about the mesh and do not look back.

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3

i can eventuelly, but that did not answer my Q

4

When wired connections are available, they are always preferable as compared to a wireless backhaul. I agree with @eduperez that you should go this route.

But that said, I'm not sure I understand your current question or constraints... can you restate/elaborate?

  • Are wired connections to all your (planned) APs available now? If not, obviously you'd use a wireless bakhaul for now and hopefully move to wired in the future, if that is an option.
  • If wired connections are in place now (or can be easily), why are you interested in wireless backhaul? (if you're thinking that you can 'bond' the wired and wireless interfaces for better bandwidth, this will not be practical/possible, and will likely make your performance worse).
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5

No, other than the comment about wires, everything else looks pretty vanilla.

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6

This is easily accomplished, you won't have much problems with it so long as your devices own roaming logic is fine. (APs can suggest devices to roam, but ultimately clients decide)

Wireless backhaul will always be a drawback, if you must mesh it's nothing technically infeasible however. For most use cases 802.11s should be fine, and for more complicated setups there's BATMAN. You'd better implement them and if you're hitting any roadblocks, come back here and ask about specific issues. OneMarcFifty on YouTube goes through how to set them up, so you can get an idea about possible configurations and how they apply to your scenario.

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7

I have watched 2 videos from OneMarcFifty. They have helped greatly in leading me to the questions that I was trying to ask but lacked the insight to frame correctly. https://www.youtube.com/watch?v=vVoZppb_FR0 and https://www.youtube.com/watch?v=kMgs2XFClaM

Each video describes a scenario

  1. Cheap Wifi Mesh alternative with fast roaming. That is router/gateway + APs connected back to router via ethernet cable using 802.11r for fast handover between APs

  2. DIY Wi-Fi Mesh with OpenWrt. That is router/gateway + APs connected back to router via a specific wifi channel. No cables. That uses 802.11s to enable the backhaul for the mesh

What I am asking about is the combination of the two. What happens if I build a variant of option 2 with one or more APs connected back to the router with a cable?

Also something that confuses me a bit is in the 2 videos 802.11r and 802.11s are mentioned but not explained in detail, so i might mix the 2 up

My situation is this. I have some cabling that can be used for wired backhaul. However it needs further preparation, so cannot be used immediately. My existing wireless mesh network has died. It worked well for the users in the house but was not based on OpenWrt. So, I want to upgrade to OpenWrt wireless mesh immediately

I will be using different hardware (Zyxel WSM20s throughout - one as a gateway router, the others as dumb APs). I will then gradually make the further upgrade of replacing the wireless back haul from one AP with an ethernet cable, then the next, etc.

eduperez said, "If you can wire them, forget about the mesh and do not look back." I assume that this is scenario 1? However, my sitation is that I need the mesh initially.

psherman then said, "......Are wired connections to all your (planned) APs available now? If not, obviously you'd use a wireless bakhaul for now and hopefully move to wired in the future, if that is an option."

The "If not" option is my situation - with the additional constraint of not being able to move all APs to wired back haul at the same time.

When I configure the backhaul interfaces to wired, does this automatically remove the 802.11s mesh functionality and revert to a situation where the AP(s) with backhaul are running 802.11r?

And, most importantly from my point of view, can an AP with wired backhaul co-exist with an AP with wireless backhaul when both are offering the same SSID and rapid switchng between APs.

If not, then I will have to ditch my plan for gradual transfer and instead work out how to do a "big bang".

8

Just to clarify:

  • 11r is a wifi standard how clients can move/roam fast between APs.
  • 11s is a wifi standard how devices can communicate without a (central) AP

Therefor you can build a mesh, in a 11s sense, and announce one or more SSID, and this mesh can offer 11r capabilities so clients can roam faster between these APs...

If you want to use both, wired and wireless connections for your APs:
Even if you build a star-topology[1] you will have a loop and have to enable and configure STP. The default timers will block your link(s) for around 20+ sec.
BATMAN-adv solves this in a more timely manner, with its loop-avoidance feature.

[1] router -> APs, no AP interconnect

If your cabling is stable and don't break two times a week.... forget about 11s, and just use the wires.
If you want to interconnect the APs, you still have to deal with STP, or using batman-adv. Again, the default STP timers are from the 80ies, and I'm not aware of any RSTP implementation available for Linux and/or OpenWRT.

If you need both, for a short time or from time to time, then like I said, either consider a "proper" STP or go with batman-adv.

11r can be useful, as others have already said, but can also just be "candy". If the roaming behavior is not good on your clients, you can setup and put on top the 11r any time later.

9

If possible, use wired connections between your routers/aps. You do not need to use 802.11s (mesh). Only use wireless connections if wired is not possible. Keep it simple.

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10

Disclaimer: I've not used 11s myself.

Yes

First of all, 11r is independent of 11s or wired dumb APs. To dumb it down hard, it simply issues a "common key" that'll let client associate with the next AP with the same SSID and PSK. It has no bearing on the backhaul or vice versa—you can have 11r whether you're doing 11s or wired.

Second of all, as you saw in the videos, 11s is a configuration you deliberately make, you need to download additional wpad-mesh packages to do this. It doesn't automatically disable once you do connect to wire, so whenever you get around to do get to wire them down the line, you need to change settings so wire is the backhaul.

Short answer, yes. It'll be complicated as @_bernd says if you've both simultaneously, but from what I see, you don't. So long as your APs can talk to each other, it's good.

11

Access points participating in a mesh ideally requires a dedicated radio used only for communicating with other mesh access points. If you want to use both 2.4 GHz and 5 GHz bands for the clients, then the mesh APs needs to have three radios. With a wired backhaul, you can use any AP (or wireless routers configured as APs).

12

They do not require it. Sure, the overall throughout is not great but most radios support 11s + AP just fine...