Question My Router selects 5 GHz instead of 2.4 GHz, why?

very_452001

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Mar 8, 2014
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Hello,

My router is TP-Link Archer AX20 v2 Router that is wi-fi 6 and dual band and my smart supposedly Ai device is also dual band and supports wi-fi 6 too. The frequencies are combined in a single SSID not separate according to my router settings.

The device is mounted on my wall outside meaning it is far away from my router. According to the smart Ai device via its app on my phone it reports Weak Signal when I see its connected to my Router via 5 GHz and Great Signal when I see its connected to my Router via 2.4Ghz.

I have issues on 5 Ghz for the device but no issues for 2.4 Ghz. The problem is I cannot choose which frequency band in the device app on my phone so why my router sometimes automatically nominates 5 GHz for a device that is far away from it? When it automatically selects 2.4 Ghz I have no issues with the device meaning I can connect to the device via its app but intermittently whenever the router feels like choosing 2.4 Ghz for it.

In my router how do I permanently set 2.4 Ghz for my device please?

Another unrelated question is lets say for example I have a PS5 console that I do online gaming via wireless wi-fi. My ISP speed is 250 Mbps. The router advertises its max speed 1000 Mbps. On both frequencies 2.4 ghz and 5 ghz frequencies the PS5 reports excellent signal with the same download and upload speeds. The question is will the online gaming performance be the same on both frequencies, no difference or will there be a difference in ping or whatever? And will the interference like turning a microwave on will affect online gaming in 2.4 ghz when channel is set to Auto in router settings?

Features of wifi 6 is available for both 2.4 ghz and 5 ghz?

Lastly does wi-fi 6 benefits battery powered devices more over mains powered devices or is it both the same?

Finally why the Real-time Rate shown in my Router settings measured in KB/s for my devices connected to it? What is the Ratio between KB/s and the ISP's 250 Mbps?
 
Last edited:
See page 14...
https://www.manua.ls/tp-link/archer-ax20/manual?p=104

You may need to disable Smart Connect

Okay so I will get 2 SSID's if I do that?
Why cant the router decide for itself that the device is far away and permanently choose 2.4 GHz for it or are most routers are 'Dumb'?

So if I disable smart connect I have to manually connect the device to the router again via the now new available 2.4 GHz SSID?
 
It is your end device not the router that decides which to connect to. Depends on the device but many you can force it to use 2.4 or 5 even with the same SSID.

You are always better off using different ssid. It depends on if you want to be in control or if you are lazy and just want the device to try to guess which is best.

Gaming on any wifi is going to get random lag spikes. Online games do not are about bandwidth, they only use about 1mbps so both the 2.4 and 5 radios are the same no matter what the maximum speed they can do. What you might do is set the 2.4 radio band to only use 20mhz channels (this is done on the router). Because their is less data being crammed into the same radio bandwidth data errors are less common. It really depends on how many neighbors you have and how active they are.

It will be trial and error to find out is 2.4 is better than 5 and what channels work the best. Unfortunately it can change minute to minute as some neighbors does somethings with their wifi.

If 2.4 work better for the game what you could then do is when you download new games or big updates switch to the 5 radio since it "should" have faster downloads.

Wifi 6 in general is smoke and mirrors. Because of all the restrictions on use 160mhz radio channels many end device do not support it. This is the key feature that makes wifi6 faster. The other feature that uses QAM1024 data encoding only really works in the same room. So without either of these feature wifi6 work pretty much the same as wifi5. Most people saw no big improvement. wifi6e is much better because there is lots of bandwidth and you can easily get 160mhz radio chanels on the 6ghz radio band.

A side node your microwave oven will not really interfere. Even thought he microwave puts out over 1000 times the power of a router the amount that is allowed to legally leave the microwave is only a tiny fraction of what a router can legally transmit at. It is surprising that you can see though the front glass and it pretty much blocks all that signal. Now if the microwave oven happens to be between your router and your pc the routers signal will be blocked by the chassis of microwave. Not a very likely thing to have happen but if you want to test is sometime set your cell phone to display the wifi power levels. Then put it in the microwave ( obviously you are not going to turn it on). You can look though the glass and you will likely see no wifi signals being detected on 2.4ghz.
 
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It is your end device not the router that decides which to connect to. Depends on the device but many you can force it to use 2.4 or 5 even with the same SSID.

You are always better off using different ssid. It depends on if you want to be in control or if you are lazy and just want the device to try to guess which is best.

Gaming on any wifi is going to get random lag spikes. Online games do not are about bandwidth, they only use about 1mbps so both the 2.4 and 5 radios are the same no matter what the maximum speed they can do. What you might do is set the 2.4 radio band to only use 20mhz channels (this is done on the router). Because their is less data being crammed into the same radio bandwidth data errors are less common. It really depends on how many neighbors you have and how active they are.

It will be trial and error to find out is 2.4 is better than 5 and what channels work the best. Unfortunately it can change minute to minute as some neighbors does somethings with their wifi.

If 2.4 work better for the game what you could then do is when you download new games or big updates switch to the 5 radio since it "should" have faster downloads.

Wifi 6 in general is smoke and mirrors. Because of all the restrictions on use 160mhz radio channels many end device do not support it. This is the key feature that makes wifi6 faster. The other feature that uses QAM1024 data encoding only really works in the same room. So without either of these feature wifi6 work pretty much the same as wifi5. Most people saw no big improvement. wifi6e is much better because there is lots of bandwidth and you can easily get 160mhz radio chanels on the 6ghz radio band.

A side node your microwave oven will not really interfere. Even thought he microwave puts out over 1000 times the power of a router the amount that is allowed to legally leave the microwave is only a tiny fraction of what a router can legally transmit at. It is surprising that you can see though the front glass and it pretty much blocks all that signal. Now if the microwave oven happens to be between your router and your pc the routers signal will be blocked by the chassis of microwave. Not a very likely thing to have happen but if you want to test is sometime set your cell phone to display the wifi power levels. Then put it in the microwave ( obviously you are not going to turn it on). You can look though the glass and you will likely see no wifi signals being detected on 2.4ghz.

On modern devices nowadays how do you force it to use 2.4 Ghz? I ask because on the app for the device I do not see a network setting to choose 2.4 Ghz..

Okay I am from UK, which channels you recommend for both 2.4 Ghz and 5 Ghz? In router in UK which channels are 20mhz only?

Okay most modern devices don't support wifi6e unless you have the latest iPhone 16 or the latest Samsung s25 or something? Is wifi 7 backwards compatible with wifi6e and is wifi 7 good as wired ethernet yet?
 
Wifi7 is mostly marketing. I does run much faster than wifi6e because it now attempts to use 320mhz radio channels rather than 160. The bandwidth pigs are again trying to use every bit of radio bandwidth for a single user thinking that none of their neighbors will also attempt to use any.

Even wifi6e is kinda stupid on a cellphone. Bandwidth only maters for very large upload/downloads. Portable devices do not have enough storage to matter. It is not like you are trying to install 100gbyte microsoft flight simulator on a iphone. Huge video rendering files is the other use of bandwidth on a local lan but again it is only large desktop machines that have the cpu and gpu power to process this. Most these large machines are connected via ethernet so wifi speed really doesn't matter for this application anyway. It is a rather niche case where someone has a large bandwidth requirement with only wifi connectivity available.

On a phone or other device that does not run a OS where you have good controls I can't say. Even on linux and windows OS if the driver from the wifi chipset maker does not have the option to force the radio band it can't be done.

I have always used different SSID. I even used different SSID for different AP radios when I was running multiple. I tend to like to be in control rather than the app.

The standard radio radio channels are 1,6,11 on 2.4. I think in the UK you can also use 13 but I would stick with 1,6,11. There should be a option in the router to run 20 or 20/40. It is also technically possible to force a 20mhz channel width on some end devices....again the driver must have the support.

I would leave the 5ghz radio in auto mode. You can force 20mhz radio mode on 5ghz but I would not really recommend it. Your bandwidth is massively reduced when you run 20mhz rather than 40,80 or 160 or even 320. Key here is you are trying to manual balance your traffic putting traffic that does not need high speed but needs high quality on 20mhz and leaving stuff that need high speed but can tolerate random delays on the wider channels.

You are always smarter than any kind of software of AI in selecting where and what you connect. Problem is many people don't want to learn anything or make any effort at all to tune thier systems so they just run with whatever setting the software chooses for them.
 
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It's best to follow whatever convention most of your neighbours are using, so if that's 1, 5, 9, 13 which most countries in the world that allow full-power on ch13 use, then do that.

This is only possible because with OFDM the "20MHz wide" bit actually means 16.25MHz so there is no overlap, and requires nobody to be using actual 22MHz wide DSSS channels as with 11Mbps 802.11b because that would then overlap.

If you must share a channel with someone else it's best to share the exact same control one and not just let it overlap, because then the stations can negotiate when to be quiet to each other, instead of just talking over each other to cause collisions and corrupt packets.

With different SSIDs you could just not enter the password for the 5GHz one into the devices you wish force to use 2.4GHz. This way it is up to you instead of your client device, and works even if the passwords are the same for convenience.
 
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Wifi7 is mostly marketing. I does run much faster than wifi6e because it now attempts to use 320mhz radio channels rather than 160. The bandwidth pigs are again trying to use every bit of radio bandwidth for a single user thinking that none of their neighbors will also attempt to use any.

Even wifi6e is kinda stupid on a cellphone. Bandwidth only maters for very large upload/downloads. Portable devices do not have enough storage to matter. It is not like you are trying to install 100gbyte microsoft flight simulator on a iphone. Huge video rendering files is the other use of bandwidth on a local lan but again it is only large desktop machines that have the cpu and gpu power to process this. Most these large machines are connected via ethernet so wifi speed really doesn't matter for this application anyway. It is a rather niche case where someone has a large bandwidth requirement with only wifi connectivity available.

On a phone or other device that does not run a OS where you have good controls I can't say. Even on linux and windows OS if the driver from the wifi chipset maker does not have the option to force the radio band it can't be done.

I have always used different SSID. I even used different SSID for different AP radios when I was running multiple. I tend to like to be in control rather than the app.

The standard radio radio channels are 1,6,11 on 2.4. I think in the UK you can also use 13 but I would stick with 1,6,11. There should be a option in the router to run 20 or 20/40. It is also technically possible to force a 20mhz channel width on some end devices....again the driver must have the support.

I would leave the 5ghz radio in auto mode. You can force 20mhz radio mode on 5ghz but I would not really recommend it. Your bandwidth is massively reduced when you run 20mhz rather than 40,80 or 160 or even 320. Key here is you are trying to manual balance your traffic putting traffic that does not need high speed but needs high quality on 20mhz and leaving stuff that need high speed but can tolerate random delays on the wider channels.

You are always smarter than any kind of software of AI in selecting where and what you connect. Problem is many people don't want to learn anything or make any effort at all to tune thier systems so they just run with whatever setting the software chooses for them.

What you mean your in control instead of the app being in control when using different separate SSID's? Control as in which SSID the device connects to?

In my router settings shall I just leave the default channel selection which is Auto? You mean the device hardware wireless networking chip and the drivers for it must support 20mhz for 20mhz to work?

So 20mhz is higher quality but slower speeds per second and 20/40 is higher speeds but quality reduced? There is no middle ground? When you say networking quality, what do you mean? Is it lower ping and no noise interference and a constant quality connection, no lags or spikes in real time graph?

Another question I have is if I enable 2.4 GHz guest mode in my router then does guest mode wi-fi has the same networking performance and quality as admin wi-fi?

I ask because the electrician mounted the device high up on my building using a tall ladder and any change in the SSID network name requires the user to go up physically to the device and press the sync button on it to sync it to the new SSID before managing it in its app.

What is your advice to prevent this crazy notion of finding a tall ladder, going up high, risk falling off just to press the sync button on the device because the user wants to use the 2.4 Ghz SSID wi-fi for better signal.

It is this device:

https://www.amazon.co.uk/eufy-Secur...mzn1.fos.d7e5a2de-8759-4da3-993c-d11b6e3d217f
 
It's best to follow whatever convention most of your neighbours are using, so if that's 1, 5, 9, 13 which most countries in the world that allow full-power on ch13 use, then do that.

This is only possible because with OFDM the "20MHz wide" bit actually means 16.25MHz so there is no overlap, and requires nobody to be using actual 22MHz wide DSSS channels as with 11Mbps 802.11b because that would then overlap.

If you must share a channel with someone else it's best to share the exact same control one and not just let it overlap, because then the stations can negotiate when to be quiet to each other, instead of just talking over each other to cause collisions and corrupt packets.

With different SSIDs you could just not enter the password for the 5GHz one into the devices you wish force to use 2.4GHz. This way it is up to you instead of your client device, and works even if the passwords are the same for convenience.

Channel 13 allows it to transmit at full power?

My router has combined 2.4 GHz and 5 GHz bands into 1 SSID wi-fi network name and same wifi password by default. Please advise.
 
Change the SSID for the 2.4 and 5 to different values.

although over simplified when you use 20mhz rather than 40mhz radio bands you have 2 times the chance someone else might interfere with the signal. If your neighbors is 40mhz channels your router tends to be able to extract the 20mhz signal. If the neighbors is also using 20mhz on the same exact channel then you can still get interference.

How guest works can vary a bit between routers. In general the way it works on most consumer devices is it is all one network they just have a firewall rule in the router that prevents the guest network from talking to other devices on the LAN. In effect it can only talk to the internet.

I really hate those so called "smart" lights. The button you call a sync button makes your whole network insecure. It uses a feature called WPS to get the password. Problem is even if you do not push a sync button on the router the router will always take the WPS code number. This code number is easily cracked by a cell phone and even worse you can never change this code.
The only somewhat safe way is to use the option in the router to completely disable the WPS feature. You can turn it on for short periods of time when they "smart" device needs to sync and then completely disable the feature.

Long term none of these devices will function. The new security key exchange called WPA3 does not allow or function with WPS. Although they might change the rules wifi7 requires WPA3 to be used.
 
Channel 13 allows it to transmit at full power?
Oh yes, only in North America is the power limited on it.

The standalone eufy cameras do not have to use WPS--there are full controls for Wifi settings in the eufy Security app for you to enter the password manually. You do have to use a sync button for models with a Homebase (a base station), but the Homebase usually connects to your network via ethernet and the button only pairs a satellite with the Homebase.

Besides, if you change only the SSID name for 5GHz in the router, any client device which is already setup will still be able to connect to 2.4GHz just as it has always done. It just will no longer be able to connect to 5GHz.
 
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Change the SSID for the 2.4 and 5 to different values.

although over simplified when you use 20mhz rather than 40mhz radio bands you have 2 times the chance someone else might interfere with the signal. If your neighbors is 40mhz channels your router tends to be able to extract the 20mhz signal. If the neighbors is also using 20mhz on the same exact channel then you can still get interference.

How guest works can vary a bit between routers. In general the way it works on most consumer devices is it is all one network they just have a firewall rule in the router that prevents the guest network from talking to other devices on the LAN. In effect it can only talk to the internet.

I really hate those so called "smart" lights. The button you call a sync button makes your whole network insecure. It uses a feature called WPS to get the password. Problem is even if you do not push a sync button on the router the router will always take the WPS code number. This code number is easily cracked by a cell phone and even worse you can never change this code.
The only somewhat safe way is to use the option in the router to completely disable the WPS feature. You can turn it on for short periods of time when they "smart" device needs to sync and then completely disable the feature.

Long term none of these devices will function. The new security key exchange called WPA3 does not allow or function with WPS. Although they might change the rules wifi7 requires WPA3 to be used.

If I change the SSID, the device will lose connection to my wi-fi meaning I have to get a tall ladder in which I don't have, to access the device mounted outside on my wall and press the sync button on it to register the new SSID to the device.

I have no clue what frequencies or channels my neighbours uses.

Lets say theres 2 users connected to the wi-fi network in the home however 1 of them is using the Guest network. Your saying for example the one on the Guest network cannot do a whatsapp video call to the other user on the main wi-fi network because of the firewall protecting LAN users from guest users? LAN means users are close to each other in the same physical location or LAN means devices can communicate with each other in the home without a ISP for the home?
 
Lets say theres 2 users connected to the wi-fi network in the home however 1 of them is using the Guest network. Your saying for example the one on the Guest network cannot do a whatsapp video call to the other user on the main wi-fi network because of the firewall protecting LAN users from guest users? LAN means users are close to each other in the same physical location or LAN means devices can communicate with each other in the home without a ISP for the home?
To over simplify it lan means other machines in your house...it gets complex when you ask what lan means in a business.

I am not sure about whatsapp.

The more common example would be people on the guest network could not get access to a file share on other pc or maybe a nas. They also can not use a printer that is on the lan. It is basically for people you can not trust that are in your house but you want to allow them to use the internet.
 
Oh yes, only in North America is the power limited on it.

The standalone eufy cameras do not have to use WPS--there are full controls for Wifi settings in the eufy Security app for you to enter the password manually. You do have to use a sync button for models with a Homebase (a base station), but the Homebase usually connects to your network via ethernet and the button only pairs a satellite with the Homebase.

Besides, if you change only the SSID name for 5GHz in the router, any client device which is already setup will still be able to connect to 2.4GHz just as it has always done. It just will no longer be able to connect to 5GHz.

The Eufy device directly connects to my router not their Homebase. I don't have Eufy homebase.

To confirm the Sync button on my Eufy device is just a 'WPS' button?

Also to confirm I only need to press the sync button on the Eufy device only if I have their homebase but not required for own router if the SSID name changes?

To change the SSID name for the 5 GHz I have to separate the 2 frequencies 1st?
 
To over simplify it lan means other machines in your house...it gets complex when you ask what lan means in a business.

I am not sure about whatsapp.

The more common example would be people on the guest network could not get access to a file share on other pc or maybe a nas. They also can not use a printer that is on the lan. It is basically for people you can not trust that are in your house but you want to allow them to use the internet.

But isn't most devices nowadays are 'smart' devices that have their own phone apps requiring internet correct? Wi-Fi printers require internet too? Any device that has firmware that can be updated through the internet requires internet WAN and not on LAN?
 
You have to split the 5g and 2.4g radio bands to set different ssid. As stated you can't really change 2.4 then change the 5. As long as they are different you can then control which you connect to.

All these devices that need to connect to the internet is why there are so many security issues. A lot of people setup a completely different network for IOT (internet of things) in their house that is isolated from their main lan.

Lan mostly means that the devices can communicate directly without leaving the house.
 
All these devices that need to connect to the internet is why there are so many security issues. A lot of people setup a completely different network for IOT (internet of things) in their house that is isolated from their main lan.

Lan mostly means that the devices can communicate directly without leaving the house.

How you completely setup a different network for IOT?

Does LAN mean any devices that is assigned a DHCP IP address by the router that can communicate each other in the same house and once you leave the house you leave your wifi and your cellphone is now using a public ip address by your cellphone data provider which is not assigned by your router?

So using the whatsapp example. If I whatsapp video call another wifi user in the same house as me also on same wifi then is it LAN or WAN?
 
The latest TP-Link firmware added a separate IOT network. Unfortunately with TP-Link you may not be able to upgrade to this if your "hardware version" is too old, but you could always just use the Guest network for IOT.

Use a phone app such as Wifi Analyzer to see what channels your neighbors have chosen, or the router itself may have a site survey tool in later firmware to accomplish the same--however note neither of these will tell you which channels actually see the most traffic (many stations on the same channel or an overlapping one are of no consequence if none of those stations actually broadcasts anything). Pick the least busy 2.4GHz channel following the convention most of the neighbours are using--but there's a good chance none of them will be good choices. 5GHz is way easier as the signal drops off so quickly that you may only be able to detect your very next door neighbours' 5GHz

If you can setup the Eufy without using the button, then it is indeed just a WPS button. You could then disable WPS in the router. TP-Link always sets the defaults to whatever is most convenient at the expense of security--for example GTK Key Renewal interval is by default "0" meaning disabled/key never expires, a security risk.

I don't understand why you would want to set the Eufy up again, when it's already working and will continue to do so as long as you don't change the 2.4GHz SSID or password. You only ever need to set clients up once in the device's lifetime unless you ever need to change either of those. You could swap out your entire router and so long as you set the new one up with the same SSID and password as before, the clients will "just work" with the new router too, exactly like before.

If you change the SSID for both 2.4GHz and 5GHz to something else but both are still the same as each other, then how are you better off than now? You get to either climb a ladder or manually configure the wifi but would end up having the same problem with 5GHz as now.
To change the SSID name for the 5 GHz I have to separate the 2 frequencies 1st?
Have you even looked in the wifi settings page (or the advanced one)? They were already separate by default and someone has changed them to match, probably by ticking that dumb "Smart Connect" box. Untick it, then change only the SSID for the 5GHz and the Eufy will never use 5GHz again. You will want to enter that new 5GHz SSID into other clients that work fine on 5GHz such as your PS5 in order to spread the load out when they are used simultaneously--you don't want everything on the same narrow 20MHz wide channel because that would be a bottleneck.

Whatsapp requires an internet connection over the WAN to the Whatsapp servers, so even two people chatting on the same local network will have each message sent to the Whatsapp cloud and back again. It does not work locally.
 
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BFG-9000 has covered most your questions.

Your question about a separate IOT network gets into what does "LAN" mean again. Most people implement this using vlans..ie "virtual" LAN. So you have added a second layer of complexity to your question. So more technically but still a bit general to avoid 1000 word answer is they are different subnets. In a home user install these subnets use different IP ranges in the private IP pools. There is some kind of firewall device that will prevent/allow communication between the different subnets, the exact rules can be anything you can think of. All these different internal subnets (ie LANS) then are translated to the external WAN ip when it goes to the internet. The actual answer is massively more complex because big companies like microsoft use public ip on their internal lans sometimes.
 
The latest TP-Link firmware added a separate IOT network. Unfortunately with TP-Link you may not be able to upgrade to this if your "hardware version" is too old, but you could always just use the Guest network for IOT.

Use a phone app such as Wifi Analyzer to see what channels your neighbors have chosen, or the router itself may have a site survey tool in later firmware to accomplish the same--however note neither of these will tell you which channels actually see the most traffic (many stations on the same channel or an overlapping one are of no consequence if none of those stations actually broadcasts anything). Pick the least busy 2.4GHz channel following the convention most of the neighbours are using--but there's a good chance none of them will be good choices. 5GHz is way easier as the signal drops off so quickly that you may only be able to detect your very next door neighbours' 5GHz

If you can setup the Eufy without using the button, then it is indeed just a WPS button. You could then disable WPS in the router. TP-Link always sets the defaults to whatever is most convenient at the expense of security--for example GTK Key Renewal interval is by default "0" meaning disabled/key never expires, a security risk.

I don't understand why you would want to set the Eufy up again, when it's already working and will continue to do so as long as you don't change the 2.4GHz SSID or password. You only ever need to set clients up once in the device's lifetime unless you ever need to change either of those. You could swap out your entire router and so long as you set the new one up with the same SSID and password as before, the clients will "just work" with the new router too, exactly like before.

If you change the SSID for both 2.4GHz and 5GHz to something else but both are still the same as each other, then how are you better off than now? You get to either climb a ladder or manually configure the wifi but would end up having the same problem with 5GHz as now.

Have you even looked in the wifi settings page (or the advanced one)? They were already separate by default and someone has changed them to match, probably by ticking that dumb "Smart Connect" box. Untick it, then change only the SSID for the 5GHz and the Eufy will never use 5GHz again. You will want to enter that new 5GHz SSID into other clients that work fine on 5GHz such as your PS5 in order to spread the load out when they are used simultaneously--you don't want everything on the same narrow 20MHz wide channel because that would be a bottleneck.

Whatsapp requires an internet connection over the WAN to the Whatsapp servers, so even two people chatting on the same local network will have each message sent to the Whatsapp cloud and back again. It does not work locally.

Okay in summary for IOT devices use Guest network for privacy & security, stop big companies stealing local data from your LAN?

Also I need to reconnect all devices clients again to the 5 GHz network if I do not change the 2.4 GHz network as advised?

During the initial setup of Eufy Cams, the Eufy Security app on phone requested me to press the 'Sync' button on the Eufy cam to complete setup even though WPS is disabled on my router however this app still asked me to input the wi-fi password so I like to know what is that 'Sync' button on the Eufy cam really for and why does it needs to be pressed again if a SSID network name changes.
 
I have not read the manual but how does the app know how to connect to the camera. Does it somehow connect directly using a different wifi connection. Can you just randomly connect to anyone's camera.

If you can use some app to set the wifi SSID and password I can't see the need to press a button. I am just too lazy to read the manual for your camera today.
 
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