As a Wi-Fi surveillance camera, the first thing we need to do to make the camera useful, is to transmit the desired Wi-Fi SSID and password to the camera.
The traditional way to handle this task, is a multi-process AP/Station mode switch. The camera first acts as a Wi-Fi access point. The user will have their mobile phone connect to the camera Wi-Fi AP, sending the desired Wi-FI SSID and password to the camera. Once the camera receives the information, it switches to station mode, and connect to the router. The user mobile phone disconnects from the camera Wi-Fi AP and re-connect to the normal router. Now the mobile app and the camera can connect remotely.
This method works reliably. But the process is long, and not user friendly.
People invents different ways to transmit the information to the camera.
Smart Config is an innovation trick first seen in TI CC3000 product line. This article (http://depletionregion.blogspot.ch/2013/10/cc3000-smart-config-transmitting-ssid.html) explains in detail how smart config works.
This trick later officially evolves to AirKiss protocol(http://iot.weixin.qq.com/wiki/document-7_1.html), which is proposed by Wechat, and adopted by many Wi-Fi chips.
There are many reasons why Smart Config will not work. This article (http://depletionregion.blogspot.ch/2014/06/smart-config-for-consumer-products.html) explains the risk, and proposes some alternatives. The alternatives including USE/BLE, which all requires additional hardware, that only use for once in the product’s life time. This is not cost effective.
About three years ago, engineers in YI Technologies, Inc. come up a different way. We encode the SSID, password, along with a few other key information, into a QR code. The QR code is generated on the mobile phone. The user then faces the QR code to the camera. The camera scans the QR code, decodes the information, connects to the network. We have been using this mechanism since then.
Compared with Smart Config, this method is very secure, as there is no information broadcast. When it works, it is extremely fast, and very user friendly. (QR Code has taken over the whole China. Yes, I know, the world is behind a bit)