HTTP/3
also: QUIC
HTTP/3 is the third major version of the Hypertext Transfer Protocol that uses QUIC as its transport layer instead of TCP, enabling faster and more reliable web communication with improved connection establishment and multiplexing.
HTTP/3 represents the latest evolution of web protocols, standardized by the IETF in 2022. It replaces TCP (used by HTTP/1.1 and HTTP/2) with QUIC, a modern transport protocol built on UDP that reduces latency and improves performance, especially on unreliable or high-latency networks.
Key improvements include faster connection setup (single round-trip vs. multiple for TCP), true connection migration (packets can traverse different network paths without reconnection), and independent stream multiplexing that prevents head-of-line blocking—where a single lost packet no longer delays all streams.
In Linux environments, HTTP/3 support is becoming standard in modern web servers and browsers. For example, a curl request with HTTP/3 might look like: curl --http3 https://example.com. Web servers like Nginx and Apache are adding QUIC/HTTP/3 support, and CDNs like Cloudflare widely deploy it.