What is difference between using iframe tag and p2p video streaming? [on hold]

Well, nowadays I studied about peer5 and p2p live video streaming. It is used to show video on websites.

And now I have one question. There is already a method to show live video streaming. It is using iframe tag in HTML5. It's too easy and useful.

Then why do people use peer5 with costing money? Someone give me help about it.