Introduction to WebRTC for Unity Developers

Web Real-Time Communication (WebRTC) is an open-source technology that facilitates real-time video, voice, and data exchange between peers over networks, supported natively by most modern web browsers but requiring a C++ library integration for programming languages like C# in Unity. Originally designed for peer-to-peer (P2P) connections, WebRTC often employs media servers in commercial applications to overcome P2P's scalability and reliability limitations, especially when handling high-bandwidth video streams. P2P networks naturally scale by utilizing participants' resources, whereas client-server architectures, common in multiplayer games, require additional servers as user numbers grow. WebRTC's effectiveness in traversing NAT and firewall barriers is enhanced by protocols like STUN and TURN, which help peers discover their public IP addresses and facilitate connections when direct P2P communication is blocked. Signaling, using tools such as WebSockets, plays a vital role in establishing connections by exchanging necessary network details between peers. Interactive Connectivity Establishment (ICE) further optimizes network path selection for media streaming, and the Session Description Protocol (SDP) ensures peers agree on codec and media parameters to maintain efficient communication. In Unity, WebRTC is not native and requires a C# wrapper, with Unity WebRTC and MRTK-WebRTC being prominent solutions for integrating these real-time capabilities into applications developed on the platform.