WebRTCSignalisierung

WebRTCSignalisierung, or WebRTC signaling, refers to the process of establishing a peer-to-peer (P2P) connection between two or more participants in a real-time communication session using the Web Real-Time Communication (WebRTC) API. Unlike traditional media streaming, which relies on centralized servers for routing, WebRTC enables direct communication between browsers or devices, reducing latency and bandwidth usage. Signaling is essential because WebRTC itself does not include a mechanism for discovering peers or exchanging session descriptions—it requires an out-of-band channel to coordinate the setup of the connection.

The signaling process typically involves exchanging SDP (Session Description Protocol) offers and answers, which describe the media streams (e.g., audio, video) and their parameters, such as codecs and network addresses. Additionally, ICE (Interactive Connectivity Establishment) candidates are shared to determine the optimal path for data transmission between peers. These exchanges are often handled via a signaling server, which can be implemented using protocols like SIP (Session Initiation Protocol), WebSockets, or even simple HTTP requests. The signaling server acts as a relay for messages but does not forward media traffic itself.

Common signaling methods include proprietary solutions like Google’s STUN/TURN servers or open standards like SIP. Modern implementations often use WebSocket-based APIs for real-time communication. The choice of signaling method depends on factors such as scalability, security, and compatibility with existing infrastructure. While WebRTC itself is secure by design (using DTLS-SRTP for encryption), the signaling channel must also be protected, often through TLS or other encryption methods, to prevent eavesdropping or tampering.

WebRTC signaling is a critical component in applications like video conferencing, VoIP, and collaborative tools, enabling seamless peer-to-peer interactions while maintaining flexibility and efficiency. Its decentralized nature reduces reliance on centralized servers, lowering costs and improving performance for end-users.