I am doing one plataform that streams video, but I want that this plataform makes live streamings in real time. How do I do live-Streaming of videos with webRTC? Do I have another alternatives?
With WebRTC usually people build p2p streaming platforms: from browser to browser.
But this may be a problem if you want to record this video, so you will need some server that can proxy video from WebRTC to WebRTC and record it.
For server you can use something like opensource Kurento (couldn't launch it), or commercial Flussonic (I'm working on it) or Wowza.
But you need to know that current WebRTC implementations are limited by supported codecs, so for example with H264 you will get only baseline.