Peer js or Google App Engine Channel API

That was the question. Now I am doing a project on peer js. faced with certain restrictions. Of the various networks the connection is not triggered. For example if you work through the various wifi. Now I look there is technology Google App Engine Channel API. I just want to understand. The problems that I encountered this technology limitations of the peer js or web rtc? And if I turn on the technology Google App Engine Channel API, it will not have if I had the same Trouble? If who faced, prompt please. thanks