WiFi AP mode Channel change and SSID Hidden features

Ritesh
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WiFi AP mode Channel change and SSID Hidden features

Postby Ritesh » Tue Dec 20, 2016 7:16 pm

Hi,

I am working on ESP32 chip and have some following questions regarding AP mode configurations.
Does ESP32 provides any API or configurations to change any channel without restarting its current working mode like in AP mode? I know that there is one channel parameter in AP mode configurations structure but not have much idea to change when AP mode is already working. Let me know if anyone has idea about this.

Also, we have one more query regarding how to hide AP SSID which should be hidden while searching I to WiFi devices lists but can be access it manually by inputting SSID.
Please let. E know if anyone has idea or clues for above questions..
Regards,
Ritesh Prajapati

Ritesh
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Re: WiFi AP mode Channel change and SSID Hidden features

Postby Ritesh » Fri Dec 23, 2016 6:11 pm

Hi,

Does anyone one has any ideas for above questions which I have asked?
Regards,
Ritesh Prajapati

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kolban
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Re: WiFi AP mode Channel change and SSID Hidden features

Postby kolban » Fri Dec 23, 2016 7:19 pm

When an access point starts, it has the ability to makes its own SSID (network identifier) known on a scan by potential stations. We can disable this by setting the "hidden" flag such that a query from stations will not list the SSID of the access point. However, if a station "knows" the access point SSID, it can still attempt to connect to it. The notion of "hidden" is "hidden from a scan". If an access point started but was "hidden" and didn't allow any stations to connect to it even if they somehow knew the SSID, it wouldn't be much of an access point :-)
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Ritesh
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Re: WiFi AP mode Channel change and SSID Hidden features

Postby Ritesh » Sat Dec 24, 2016 7:10 pm

kolban wrote:When an access point starts, it has the ability to makes its own SSID (network identifier) known on a scan by potential stations. We can disable this by setting the "hidden" flag such that a query from stations will not list the SSID of the access point. However, if a station "knows" the access point SSID, it can still attempt to connect to it. The notion of "hidden" is "hidden from a scan". If an access point started but was "hidden" and didn't allow any stations to connect to it even if they somehow knew the SSID, it wouldn't be much of an access point :-)
Hi, Thanks for Reply.

OK. Got you point and understood it..I haven't tried it but I just looked that there is one hidden flag to hide SSID in AP mode WiFi configurations.
I will try and let you know if need any help for that.

Also, do you have any idea to change channel at runtime for AP mode? As I have e looked that there is one channel parameter in AP mode configurations which can set whatever channel you want to set. But, for example I have started WiFi AP mode with channel 12 and right now WiFi AP mode started. So, now I need to stop WiFi AP mode then change channel from 12 to 10 and again need to start AP mode. Correct?

Let me know if I am wrong at any place
Regards,
Ritesh Prajapati

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kolban
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Re: WiFi AP mode Channel change and SSID Hidden features

Postby kolban » Sat Dec 24, 2016 8:05 pm

Ive personally never studied WiFi channels and have always set my ESP32 to channel 0 and forgotten about it. Do you have any knowledge or indication that a channel that is used by an access point "can" or "should" be changed while that access point is running? It may very well be that a channel property of an access point is meant to be fixed at the point when the access point becomes active.

What is the thinking behind the question? Can you describe your design and thought process where an access point channel may wish to be changed while that access point is itself active?
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Ritesh
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Re: WiFi AP mode Channel change and SSID Hidden features

Postby Ritesh » Sun Dec 25, 2016 2:26 am

kolban wrote:Ive personally never studied WiFi channels and have always set my ESP32 to channel 0 and forgotten about it. Do you have any knowledge or indication that a channel that is used by an access point "can" or "should" be changed while that access point is running? It may very well be that a channel property of an access point is meant to be fixed at the point when the access point becomes active.

What is the thinking behind the question? Can you describe your design and thought process where an access point channel may wish to be changed while that access point is itself active?
I think WiFi channel should not be changed in AP mode after starting WiFi into AP mode as per my thinking. So, for that I have to first stop WiFi using wifi set mode or WiFi stop API and then have to change channel whatever you want to set. After that start WiFi in AP mode again which should be started with your configured channel.

So, My Aim his to change channel at runtime without restarting ESP module. It might be just need to restart WiFi which is already running into default configuration.
Regards,
Ritesh Prajapati

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