Restfull Controller

I am wanting to create a restful controller which interacts with a COM dll object, I this controller to call the methods from within the COM object and return the results in json. As I want different UI to interact with the controller.

I want to be able to call the controller from a VB app and it handle the data, and I also want a web page to display the same data.

With Yii would I set up a restful controller for each different types of controllers, ie. customers, addresses, orders etc?

Would I get my normal controller to call the restful controller and process its data, or would I use the restful controller as the web controller?

I have no knowledge of restfulness so any help would be greatly appreciated.