My WebRTC experiments

I am trying on WebRTC. I will update my progress here. Currently, I am stuck on the following issue.

When  I am using RTCDataChannel.send method, I am getting the following error:

Uncaught InvalidStateError: An attempt was made to use an object that is not, or is no longer, usable.

I am checking if this is because of the createOffer issue.

Those who are not familiar with webRTC, you can get idea from webrtc.org