[webrtc] how to send and receive "RTCSessionDescription" in c# i'd like to Webrtc communication in Unity. but i couldn't know how to signaling using webrtc in c#
You need to run a signaling server so your peers could find each other and initiate a webrtc connection. There is no standard solution, you would need to choose one or write your own. This one might be used as a starting point: https://github.com/aljanabim/simple_webrtc_signaling_server You can use any c# websocket library to communicate with it.