Ksssht, over: Walkie-Talkies and WebRTC ingest signaling

Real-time communication has come a long way, drawing inspiration from traditional methods such as walkie-talkies. WebRTC is a collection of protocols and APIs that enable real-time media (audio and video) with low latency. It differs from chunked streaming protocols like HLS and DASH, which prioritize high quality and cost-effective distribution but have higher end-to-end latency. WebRTC is designed to optimize for low latency above all else, making it ideal for applications such as video chat or teleconferencing. The main challenge with WebRTC interoperability lies in signaling, which involves exchanging key information between participants to establish connectivity and start sending media back and forth. While there are standards for content and order of SDPs, the transport method is left open-ended. This can lead to proprietary methods of exchanging SDPs, making certain types of interoperability challenging. To address this issue, WHIP (WebRTC-HTTP Ingest Protocol) aims to provide a convenient ingest workflow similar to RTMP while maintaining the benefits of WebRTC. By narrowing the scope to only ingest or video contribution workflows, WHIP can make useful simplifying assumptions and use an HTTP POST request to send an SDP offer and receive an SDP answer in the response. This allows for a well-defined endpoint for WHIP client configuration and enables media to be ingested using WebRTC. WHIP is still a work in progress, but it has the potential to benefit various applications and services that require real-time communication with low latency.