Fast / seamless roaming through ethernet with OpenWRT

Hardware Questions and Recommendations
1

Hi,

in my house I want to have only one WiFi network through four wired APs. So I reasearched a bit and found that I need a feature which is (sometimes) referred to as "fast roaming" or "seamless roaming".
Is OpenWRT supporting this somehow?
Is OpenWRT supporting this through cabled connections?

The situation:
Currently I am renovating a house that I bought and planning the WiFi network right now.
I am using OpenWRT on my router for several years now, so I got some experience with flashing and configuring.

This is why I am looking for OpenWRT capable APs.
The house has four floors (cellar, groundfloor, first and attic).
I placed network cables at all relevant locations, so I just need WiFi for mobile devices.
There is also one network cable for APs in good locations (only one wall to the other rooms) on each floor, so I can use PoE APs.

I still have my old Archer C5 as router and plan to use ZyXEL NWA50AX Pro as AP.

Thanks,
Leisereiter

3

I’ve written about this recently.

Happy to answer any questions or continue the conversation. The tl;dr is that you may be best served by not using 802.11r.

2 Likes
4

to add to the tl;dr

…, unless one is also using 802.1x with external authentication.

5

Thanks all for the extremely quick answers!

does this mean I will have four SSIDs in my house? I want to avoid that as this might not be accepted by my wife.
Or will I set up all four APs individually with same SSID, same settings and same WiFi password?

Thanks
Leisereiter

6

Yes you can set it up with the same network name and password. You will see one network.

7

I Agree - basic (non-FT) roaming is already quite fast (except when using 802.1X/EAP). So unless you are walking around your house while in a Zoom/Teams session I would suggest to stick to the KISS principle and not enable 802.11r

These reports

are mentioning following delays (when I interpret them correctly)

  • roaming delay non-FT 150ms (PSK)
  • roaming delay non-FT 500ms+ (EAP)
  • roaming delay FT 16-71ms
2 Likes
8

Thanks so much for your help.
I will go without the FT roaming for now, just setting up the APs and see how it works.

9

Unless you have VLANs, you'll have a single SSID for your entire home. Devices will roam between the APs as they move around.

I'd highly recommend that you watch the video that I linked in the thread I referenced above -- it goes through the principle of how to configure APs for high performance roaming. The basic concept is:

  • All APs will broadcast the same SSID and use the same passphrase.
  • Neighboring APs should be set so that they are using non-overlapping channels
  • Power levels should be reduced on all APs to minimize the amount of overlap in the coverage of each AP.
  • Ideally, you'll also deploy the devices in strategic locations to optimize coverage and performance.

Yes, the family factor is always important. Make sure that you set expectations so that family knows when you'll be messing with things -- much better than them being surprised.

1 Like
10

The other reason to have 802.11r in addition to teams etc. is interactive gaming in style of Clash of clans, where a war may get interrupted/defaulted/autoplayed to end if your phone decides to roam in the middle. 802.11r handles that nicely while ordinary basic roaming may quite much longer in reality than vendors claim.

I have got burned by that a few times even when already sitting down...

Properly weak signal strengths do help, as your phone roams early enough, right after you have moved.

3 Likes
11

The video is really useful.
I guess I will need to play with the parameters and find the best combination.

12

I have a question here: What if devices with different specs using 802.11r on same SSID? For example, my main working area of course would be putting the best 802.11ax (maybe 4x4 160MHz), and then the other floor due to low usage I am putting an older 802.11ac (1x1) one, will this work?

13

It does. I have used R7800 with ac and RT3200 with ax.

1 Like