QUIC
A UDP-based, TLS-integrated transport protocol that powers HTTP/3 and DNS over QUIC, offering faster setup and better loss recovery than TCP.
QUIC is a transport protocol built on UDP that bundles connection setup, encryption (TLS 1.3), and reliable, multiplexed streams into a single design. Each QUIC stream is independent, so a lost packet on one stream does not block the others (no TCP-style head-of-line blocking). Connections survive IP changes (handy on mobile), and 0-RTT resumption skips the handshake entirely for repeat visits. QUIC is the foundation under HTTP/3 and DoQ. Some corporate firewalls still block UDP/443 wholesale, which forces clients back onto HTTP/2 over TCP.