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Re: Communication without Internet

Wed Apr 06, 2016 6:09 am

A self-hosted AP can create an open WiFi, which enables devices
who chose to join it to communicate with the AP freely.

The AP can run a captive portal which enables to switch the
AP into a WiFi client if an WPA key and another
SSID are provided.
Even commercial products employ this technique.

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Re: Communication without Internet

Wed Apr 06, 2016 11:07 am

Yes you can. You use the pi in self hosted standalone AP mode at first so you connect to the pi from your phone using your fixed preset SSID and password you have set up, or even open wifi with no password. Then write the data you need, that houses SSID + pass into a web form for example. Then have the pi switch from AP mode to normal wifi clint on that house's wifi network, and now you do have network access. This does work.

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Re: Communication without Internet

Sat Apr 09, 2016 5:27 pm

presish wrote:So let me clear this up a bit...

I want to setup the WiFi on my raspberry pi. My raspberry pi is enclosed in a device. Is there a way for me to send the WiFi SSID and passphrase to the RPi via my phone or computer?

RPi - needs WiFi SSID and passphrase transmitted to it wirelessly
Phone/Computer - connected to internet and wants to send SSID and passphrase to the RPi

1) Is there a way to communicate SSID and passphrase to the RPi without a network connection from my phone/computer?
2) I know bluetooth is one method but do you know how to send SSID and passphrase? I only see examples for sending files.
You could write a script, including the SSID and passcode, to connect the Pi and send it as a file via bluetooth. And then have to Pi execute the script.

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Re: Communication without Internet

Tue Apr 12, 2016 5:36 am

presish wrote: The self hosted AP makes sense, but could I pass SSID/passphrase if I were to take the RPi into someone else's home? I want to be able to plug the RPi into any random home and send SSID/passphrase to the RPi wirelessly. Then when the RPi receives the info it will connect to the Wifi network corresponding to the SSID/passphrase give. I would need to be able to repeat the procedure in anyone's home. I need my phone to "talk" to the RPi without the RPi being on any network connection. Is this possible?
It sounds to me like you're getting requirements mixed up with implementation.

Is it an actual requirement that you need the Pi to connect to an existing WiFi network? In that case you will have the problem of getting the SSID/passphrase onto the Pi.

Or is your requirement that you walk into someone's home, plug in the Pi, and can connect to it wirelessly? If that is your requirement, the configuring the Pi as an access point as several people have suggested will work, and any existing Wifi network in the vicinity is quite irrelevant.

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Re: Communication without Internet

Wed Sep 14, 2016 1:32 pm

Well what I do is activate a mobile hotspot on my phone and have the pi waiting to connect to the hotspot....

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