HTTP/3, answered.
Everything you wanted to know about HTTP/3 and QUIC, in plain language.
HTTP/3 FAQ
What is HTTP/3?
HTTP/3 is the third major version of HTTP. It runs over QUIC, a transport protocol built on UDP, instead of TCP.
What is QUIC?
QUIC is a secure, multiplexed transport protocol. It merges the transport and TLS handshakes and avoids TCP's head-of-line blocking.
Do browsers support HTTP/3?
Yes. All major modern browsers support HTTP/3 and use it automatically when a server advertises it.
Do I need to change my website?
No. HTTP/3 is handled by the web server. Your pages and application code stay the same.
How do visitors discover HTTP/3?
The server sends an Alt-Svc header over HTTP/2 or HTTP/1.1; the browser then switches to HTTP/3 on following requests.
What if UDP is blocked?
Browsers fall back to HTTP/2 over TCP automatically, so nothing breaks.
Is HTTP/3 secure?
Yes. QUIC always uses TLS 1.3 encryption.
Which LiteSpeed products support HTTP/3?
LiteSpeed Web Server, LiteSpeed Web ADC and OpenLiteSpeed all support HTTP/3 out of the box.
Switch to LiteSpeed
in minutes.
Choose your edition, activate over SSH, and start serving faster. Transparent pricing, no setup fees, engineers on call 24/7.
