Why does my Airport Wi-Fi Network hierarchy change sometimes ?

[techwarrior]

Would they all work with the 5GHz network... or should I just leave things as it is..?

I did a wee bit of re-config on my WiFi. I have been meaning to do this for some time, and thanks be to your inquiries, it got me motivated to make some fixes on my own network.

I ran speedtest on my iPhone 7Plus in various locations in my home and I consistently get 59+ Mbps anywhere in my home on the 5G network, and 18- 52 Mbps on 2.4G. My ISP service is 50Mbps, so this is a very good result! The areas where 2.4 is "slower" are areas where I get the most interference from my two neighbor's 2.4G network. I manually set the channels on the 2.4 rather than use automatic, so that my channels avoids the same channels as my neighbors, and avoid overlapping with my own APs. A little more tweaking and I might get 50+ on 2.4G everywhere...

Using Airport Utility, I set the channel to 1, 6, 11 on my three devices broadcasting 2.4, and chose which one based on interference from other networks at each AP location. The 2.4G channels use +- 2 so if you set one to 11, it will use 9-13. Set another to 6 and it will use 4-8, etc. So, in your case if you do use a second Airport device, and manually set the 2.4 channels to avoid overlap, you might help your situation out even more (it made a world of difference for me).

If your 5G SSID is different than the 2.4, you can choose which one to connect to based on best speeds at each location. My experience suggests 5G gives me better speeds everywhere, that is what I use on devices that can use 5GHz. Looking at your list, all should support 5GHz, though I have no experience with Samsung SUHD. You will know if you try to connect to the 5G SSID and it is not present, then either the signal is too weak, or the device only supports 2.4GHz. Keep in mind, 5GHz range is somewhat less than 2.4, so you may find some locations work better with 2.4G.

In the US (I think this is a global app), we have an iOS app called Speedtest by Ookla. it is a freebie app for iOS, ATV4, and the website speedtest.net can be used on any device with a web browser. So, if you run speedtest while connected to each network (2.4 or 5G), you can determine the best network for that device at that location. For the Gen 2 & 3 ATVs that cannot run the speedtest app, run it on an iPhone standing near the ATV to determine which network SSID is better for that location.

A note on my config, I have 4 Airport devices, a Time Capsule (ac router), an Extreme (connected with Ethernet direct to Time Capsule), an Express (connected with Ethernet over powerline), and an Express (connected with Ethernet direct to Time Capsule). This 4th device has WiFi disabled, I connect an Aux cable to a speaker when I want to Airplay tunes to the patio. My home is 2 story, about 2000 Sq Feet on each level. The TC and Extreme are on opposite ends of the lower level, the two Expresses are on the upper level.

 

[mpainesyd]

Create a Wireless Network using the same network name and password as the main Extreme. With 2 Access Points creating WiFi networks with the same credentials, mobile devices will roam and use the strongest signal but they won't interfere with each other as much as with Wireless extending.

It seems that with Sierra this is not working. If I move my Macbook to another part of the house it stays connected to the original Time Capsule. The resulting signal is poor (Option-click on wifi icon and look at TX Rate). If I select "Join other Network" and select the SSID and enter the password it connects to the nearby Time Capsule and gets a much stronger signal. I am thinking of using different SSIDs for each Time Capsule so I can easly see which one I am connected to but from the above discussions, this may not work as expected.

Wifi Explorer shows the nearby Time Capsule as a strong signal and the other one as weak.

BTW my Time Capsules are connected by ethernet and one is connect to my ISP router by ethernet. They are both set to "Bridge Mode" and "Create a wireless network". It has worked well for years - it seems until Sierra came along!

 

[belvdr]

I have not had this issue in Sierra. We have an several Apple devices that roams seamlessly, although we have Linksys network devices, not Apple.

It would be interesting to find Apple devices don't roam well with Apple network devices, but do so fine with Linksys.

 

[mpainesyd]

I have not had this issue in Sierra. We have an several Apple devices that roams seamlessly, although we have Linksys network devices, not Apple.

It would be interesting to find Apple devices don't roam well with Apple network devices, but do so fine with Linksys.

OK - I experimented with renaming the SSID of one of the TCs and, as expected, it did not automatically swap between TCs. I tried deleting both wifis from the "preferrred networks" list in Network Preferences and then added them back in (and moved them to the top of the list). That made no difference (always logged in to the first in the list - not unexpected). At least I could easily select the closest TC from the wifi menu.

I then reverted the SSID to the original (common) name. That now seems to work sometimes - the Macbook usually connects to the strongest TC but not always. Sometimes I need to "Join other network" by entering the SSID and password in order to connect to the nearby TC.

So it seems my Macbook is not roaming between TCs. This might happen to other Mac/TC users but they might not realise because the connection speeds seem OK (but try doing a big Time Machine backup!).