WebTransport is a protocol framework that enables clients constrained by the Web security model to communicate with a remote server using a secure multiplexed transport.
Currently, Web application developers have two APIs for bidirectional communications with a remote server: WebSockets and RTCDataChannel. WebSockets are TCP-based, thus having all of the drawbacks of TCP that make it a poor fit for latency sensitive applications (head of line blocking, lack of support for unreliable data transport). RTCDataChannel is based on SCTP, which does not have these drawbacks; however, it is designed to be used in a peer-to-peer context, which caused its use in client-server settings to be fairly low. WebTransport provides a client-server API that supports bidirectional transfer of both unreliable and reliable data, using UDP-like datagrams and cancellable streams.
Docs: https://web.dev/webtransport/ https://docs.google.com/document/d/1UgviRBnZkMUq4OKcsAJvIQFX6UCXeCbOtX_wMgwD_es/edit
Explainers: https://github.com/WICG/web-transport/blob/master/explainer.md