HTTP/3
Topics: HTTP
HTTP/3 carries HTTP over QUIC, which uses UDP as its transport.
Successor to HTTP/2. Previously known as “HTTP-over-QUIC”.
QUIC was originally a Google effort to improve HTTP/2 by transporting it encrypted over UDP. In 2016, the IETF began working to standardize the protocol. Part of that process involved splitting QUIC into the transport protocol (QUIC) and the application protocol (HTTP/3).
Subtopics
Differences between HTTP/3 and HTTP/2
The main difference is HTTP/3 uses QUIC, which is is built on UDP, while HTTP/2 uses TCP. In addition, HTTP/3 uses QPACK to compress headers, while HTTP/2 uses HPACK to compress headers.
Thanks to its use of QUIC, HTTP/3 reduces the Head of Line blocking issue. All TCP-based protocols suffer from HoL blocking, including HTTP/2.