Sending wifi connection info to an unconnected device

Question

Is there a way to use a wifi connected device (phone, tablet, PC...) to send the required connection info (SSID, password) to an unconnected device through the same network? I'm prompted to ask the question after reading the following text from this link (http://myube.co/smart-dimmer):

The first time you launch the Ube app, you’ll be prompted to select your Wi-Fi SSID and then to enter your Wi-Fi password (if you have one – and we hope you do.) The Ube app will encrypt and send this information to the Ube dimmer The dimmer will join your Wi-Fi network and then you’ll see a notification in the Ube app that a new dimmer was found.

Maybe they are using something other than wifi to send the connection info?

I'm trying to design a device that will have no UI and may not even be user accessible (ie. no QSS button) but will need to connect to the wifi. Is there another way to do this?

Answer 1

From their FAQ:

How do you connect the dimmers to your wifi network?
During setup of your first Ube dimmer, you will need to join the Ube Wi-Fi network. You must provide the SSID and password to your home network one time in the Ube app. When you install subsequent dimmers, the SSID and password information is passed automatically from one dimmer to the next.

Emphasis mine. New dimmers create an access point (AP Mode). Once you join and run the app, they switch into client mode instead.

Other setups, like the WPS some routers, do the opposite. Your Computer creates a specially crafted network name, the router scans it, and the information is picked up that way.

Answer 2

You cannot send or receive anything through a Wifi network if the AP is configured to require authentication, which is pretty standard nowadays. So you cannot send the SSID & the password required to join a Wifi network through that particular network (SSID). If we assume that the AP running the Wifi network to be used is out of administrative control, and may require whatever authentication it chooses, the only way to exchange data via Wifi in a foolproof way is to run another AP with a different SSID. Either the the box runs an AP with a predefined or recognizable SSID, and the app joins that, or the app runs an AP and the box joins that.