Facebook Inc. Apple Inc. Apple Inc. Google Facebook Inc. WebTransport [OVERVIEW] is a protocol framework that enables clients constrained by the Web security model to communicate with a remote server using a secure multiplexed transport. This document describes a WebTransport protocol that is based on HTTP/2 [RFC7540] and provides support for unidirectional streams, bidirectional streams and datagrams, all multiplexed within the same HTTP/2 connection.