Need to send data without using http protocol with only HTML and Javascript

My requirement is to develop an RTC P2P web app. Condition to develop are.,

• Using only HTML and any Javascript library.
• Without using HTTP Protocal.
• Should work without internet, should communicate through same WIFI or LAN.
• No centralized server. For the first time, it is ok to get the client data from the server through ajax.

I have tried Socket.IO but it is using HTTP protocol and also it needed a centralized server.

Need to know any javascript library is available to work like this.