@TP-Link 

Dear,

Disabling mesh technology to a specific device (eg, my mobile) doesn´t change anything. Device still roaming between bands (5.0 to 2.4 ghz) and also moved by Decos. 

Now, about create a guest network, there are two problems:

1) Guest network is an isolate network. So if some devices are connected in 2.4, the devices in 5.0 will have no connectivity.

2) Enabling guest network doesn´t make sense since if you buy a mesh system, you´re interested to have only one SSID in your network and seamless roaming.

Here's an example of what is happening in my network:

If you check the device MAC XX:XX:XX:XX:E2:80 , you can see that the device is diassociated from ath1, which is 5.0 band and associate in ath0, 2.4 band.

Tue Dec  8 22:46:42 2020 daemon.notice nrd[21376]: wlanifBSteerEventsHandleBeaconReport: Beacon report from XX:XX:XX:XX:E2:80: APId 255 ChanId 36  ESSId 0   rcpi: 74
Tue Dec  8 22:46:42 2020 daemon.notice nrd[21376]: stadbEntry_modifyTriggerThreshold: For client XX:XX:XX:XX:E2:80 RSSI: 26 | RCPI: -73 | threshold RSSI: 37
Tue Dec  8 22:46:46 2020 daemon.notice nrd[21376]: estimatorPerformMeasurement: Do 11k measuremrent for XX:XX:XX:XX:90:37 on channel 36 from serving BSS APId 255 ChanId 3   ESSId 0  
Tue Dec  8 22:46:46 2020 daemon.err nrd[21376]: estimatorCmnHandleBeaconReportEvent: Invalid beacon report for XX:XX:XX:XX:90:37
Tue Dec  8 22:46:49 2020 authpriv.notice dropbear[4159]: Pubkey auth succeeded for 'root' with key sha1!! 47:a8:80:74:7b:e1:84:b2:54:94:eb:97:ba:a2:3d:bb:61:5d:34:f5 from 192.168.2.1:51022
Tue Dec  8 22:46:50 2020 authpriv.notice dropbear[4187]: Pubkey auth succeeded for 'root' with key sha1!! 47:a8:80:74:7b:e1:84:b2:54:94:eb:97:ba:a2:3d:bb:61:5d:34:f5 from 192.168.2.1:51023
Tue Dec  8 22:46:50 2020 daemon.notice nrd[21376]: wlanifBSteerEventsHandleNodeAssociatedInd: Node XX:XX:XX:XX:E2:80 associated on APId 255 ChanId 3   ESSId 0  , Capabilities: BTM RRM  , Max bandwidth: 0, Num of spatial streams: 2, PHY mode: 8, Max MCS: 15. Max TX power: 20
Tue Dec  8 22:46:50 2020 daemon.notice nrd[21376]: wlanifLinkEventsCmnGenerateDisassocEvent: Client XX:XX:XX:XX:E2:80 disassociated on APId 255 ChanId 36  ESSId 0  
Tue Dec  8 22:46:50 2020 daemon.err client_mgmt: wireless client associate or disassociate.
Tue Dec  8 22:46:50 2020 daemon.err client_mgmt: client_mac:4E-E3-85-91-E2-80, client_ifname:ath0, client_action:associate
Tue Dec  8 22:46:50 2020 daemon.err client_mgmt: client(4E-E3-85-91-E2-80) assocaite by if(ath0).
Tue Dec  8 22:46:50 2020 daemon.err client_mgmt: wireless client associate or disassociate.
Tue Dec  8 22:46:50 2020 daemon.err client_mgmt: client_mac:4E-E3-85-91-E2-80, client_ifname:ath1, client_action:disassociate
Tue Dec  8 22:46:50 2020 daemon.err client_mgmt: client(4E-E3-85-91-E2-80) disassocaite by if(ath1).
Tue Dec  8 22:46:52 2020 daemon.notice nrd[21376]: estimatorPerformMeasurement: Do 11k measuremrent for XX:XX:XX:XX:E2:80 on channel 36 from serving BSS APId 255 ChanId 3   ESSId 0  
Tue Dec  8 22:46:52 2020 daemon.notice nrd[21376]: wlanifBSteerEventsHandleBeaconReport: Beacon report from XX:XX:XX:XX:E2:80: APId 0   ChanId 3   ESSId 0  bssid B0:BE:76:CA:41:DA rcpi: 62
Tue Dec  8 22:46:52 2020 daemon.notice nrd[21376]: wlanifBSteerEventsHandleBeaconReport: Beacon report from XX:XX:XX:XX:E2:80: APId 255 ChanId 3   ESSId 0   rcpi: 116
Tue Dec  8 22:46:52 2020 daemon.notice nrd[21376]: wlanifBSteerEventsHandleBeaconReport: Beacon report from XX:XX:XX:XX:E2:80: APId 255 ChanId 36  ESSId 0   rcpi: 76
Tue Dec  8 22:46:52 2020 daemon.notice nrd[21376]: stadbEntry_modifyTriggerThreshold: For client XX:XX:XX:XX:E2:80 RSSI: 39 | RCPI: -52 | threshold RSSI: 35
Tue Dec  8 22:46:52 2020 daemon.notice nrd[21376]: estimatorPerformMeasurement: Do 11k measuremrent for XX:XX:XX:XX:90:37 on channel 36 from serving BSS APId 255 ChanId 3   ESSId 0  
Tue Dec  8 22:46:52 2020 daemon.err nrd[21376]: estimatorCmnHandleBeaconReportEvent: Invalid beacon report for XX:XX:XX:XX:90:37
Tue Dec  8 22:46:58 2020 daemon.notice nrd[21376]: estimatorPerformMeasurement: Do 11k measuremrent for XX:XX:XX:XX:90:37 on channel 36 from serving BSS APId 255 ChanId 3   ESSId 0  
Tue Dec  8 22:46:58 2020 daemon.notice nrd[21376]: estimatorPerformMeasurement: Do 11k measuremrent for XX:XX:XX:XX:E2:80 on channel 36 from serving BSS APId 255 ChanId 3   ESSId 0  
Tue Dec  8 22:46:58 2020 daemon.notice nrd[21376]: wlanifBSteerEventsHandleBeaconReport: Beacon report from XX:XX:XX:XX:E2:80: APId 255 ChanId 3   ESSId 0   rcpi: 108
Tue Dec  8 22:46:58 2020 daemon.notice nrd[21376]: wlanifBSteerEventsHandleBeaconReport: Beacon report from XX:XX:XX:XX:E2:80: APId 0   ChanId 3   ESSId 0  bssid B0:BE:76:CA:41:DA rcpi: 66
Tue Dec  8 22:46:58 2020 daemon.notice nrd[21376]: wlanifBSteerEventsHandleBeaconReport: Beacon report from XX:XX:XX:XX:E2:80: APId 255 ChanId 36  ESSId 0   rcpi: 76
Tue Dec  8 22:46:58 2020 daemon.notice nrd[21376]: stadbEntry_modifyTriggerThreshold: For client XX:XX:XX:XX:E2:80 RSSI: 39 | RCPI: -56 | threshold RSSI: 39

Thank you

@TP-Link 

I have seen many reactions from TPlink about using the guest WiFi for 2.4 and the main with 5. But because of the reasons in this thread we don't want that.

Please listen to your clients and give us the option to split the 2.4 and 5 band.

Another solution is that we can choose in the app if a device is "allowed" to use the 2.4 or the 5 or both bands. 

That way we can decide which device is allowed to use which band.

@TP-Link 

I would like to see your reply about this issue. Thank you

Same here on Deco M5 with firmware 1.5.1 . 5ghz capable devices (phone and laptop basically) in my home switch to 2.4ghz when further than 5m or behind wall. This band is really congested here and I get speeds way below acceptable which make streaming videos to buffer very often, video calls lag and being an awful quality and web pages taking a while to load. It used to work great, the new threshold to switch from 5 to 2.4 is too high: I prefer weaker signal with high speed than great signal with speed close to 56k era. No solutions provided work, and none should be applied anyway: TP-Link broke something in their algorithm and they should fix it, period! Or allow us to downgrade. Yes, network optimization is useless: who cares if 2.4 channel is congested, we want 5ghz! Thank you for fixing ASAP!

Antoon wrote

Same here on Deco M5 with firmware 1.5.1 . 5ghz capable devices (phone and laptop basically) in my home switch to 2.4ghz when further than 5m or behind wall. 

@Antoon 

For laptop specifically, you can check if its network driver allows to choose what band it can use. For some network drivers, It could even be preferred band, depending on network adapter you have.

If it does, you could make it only use 5GHz or prefer 5GHz. 

Example:

PS. Also see "Roaming aggressiveness" setting in that example, if your laptop has it you could increase aggressiveness to force laptop switch to node with stronger signal sooner. Will be useful if you occasionally take laptop with you around the house.

@Antoon 

Hello @Antoon ! Just to let you know, I tried several times to fix this bug somehow but unsuccessfully. It looks around -70 dbm, Deco prefers to go down to 2.4 GHz. Some devices you can not force or at least set to prefer 5 GHz, like cellphones and some other devices, except PCs. I agree with you that who purchase a mesh system always want to use 5ghz instead 2.4 to enjoy high speed. I have an opportunity to change my devices. Previous set was M5 v2 CA (Canada) and move to M5 v1 US, which shows that signal is strong and reliable. In same places that my devices used to switch before to 2.4 Ghz (90 Mbps troughput), now stay in 5Ghz (300 Mbps throughput).

@Alexandre. 

Thanks for explaining this. However, as stated in my previous comment, I do not want to deal with this at a device level: I have Windows, MacOS and Linux computers, same variety for mobile devices, it is not an acceptable option. I chose the M5 to set and forget, and it used to work great that way.

I ended up wiring everything possibe, so now all computers are ok (less the mobility for laptops). And now, when I have a crappy connection on my phone, I just turn off wifi and switch to my cell service. Luckily I have good service, but not everyone has this chance.

@IgorRJ 

I think mine is V2 US. Are you saying V1 does not have the 5Ghz band steering issue?