Web Development
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What is HTTP/3?
The latest HTTP version that uses QUIC instead of TCP, providing faster connections and better performance on unreliable networks.
HTTP/3 replaces the TCP transport layer with QUIC (based on UDP), solving TCP's head-of-line blocking problem at the transport level. Benefits include faster connection setup (0-RTT or 1-RTT vs TCP's 3-way handshake + TLS), better performance on lossy networks (a lost packet only affects its stream, not all streams), connection migration (maintaining connections when switching from WiFi to cellular), and built-in encryption. Major browsers, CDNs (Cloudflare, Fastly), and web servers support HTTP/3. Configuration in Nginx requires the quic module. HTTP/3 is especially impactful for mobile users and high-latency connections.