Recently, while utilizing a certain tool, I discovered that the latency based on UDP protocol is significantly low, and the speed feels notably swift. Consequently, I delved into understanding the HTTP/3 protocol, making my website fully compatible. Concurrently, I conducted a feature comparison, elucidated the support situation for both clients and servers, and provided configuration examples.
| Feature | HTTP/1.1 | HTTP/2 | HTTP/3 |
|---|
| Multiplexing | No | Yes (Header Multiplexing) | Yes (Multiplexing) |
| Header Compression | No | Yes (HPACK) | Yes (QPACK) |
| Priority | No | Yes | Yes |
| Server Push | No | Yes | Yes |
| Pipelining | Yes (Limited) | No | No |
| 0-RTT | No | No | Yes |
| Connection Reuse | Yes (Limited) | Yes | Yes |
| Error Recovery | No | No | Yes |
| Security | No (Plain Text Transmission) | Yes (TLS) | Yes (TLS in QUIC) |
| Transport Protocol | TCP | TCP | QUIC (Based on UDP) |
Detailed explanation of performance features of HTTP protocol versions:
Multiplexing: Allows simultaneous transmission of multiple requests and responses over a single connection, enabling parallel sending and receiving, thereby enhancing network utilization and performance.
Header Compression: Reduces the size of header information in HTTP requests and responses, thereby reducing the amount of transmitted data, saving bandwidth, and reducing loading times.
Priority: Enables clients to specify the priority of requests being sent, allowing servers to prioritize processing accordingly, optimizing resource allocation and enhancing user experience.
Server Push: Servers can proactively push relevant resources to clients before client requests, reducing the number of requests initiated by clients and speeding up page loading.
Pipelining: Allows clients to send multiple requests over a single connection without waiting for responses. However, in HTTP/1.1, the use of pipelining is limited, as not all browsers and servers support it.
0-RTT: Zero round-trip time handshake, allowing clients to reduce handshake latency by sending encrypted data when establishing a new connection. This speeds up the connection establishment process, enhancing performance.
Connection Reuse: Enables multiple HTTP requests and responses to be transmitted over the same TCP connection, reducing the overhead of establishing and closing connections, thereby improving performance.
Error Recovery: Provides mechanisms for recovery in case of errors during transmission, ensuring reliable data transmission.
Security: Ensures the secure transmission of data. HTTP/2 and HTTP/3 encrypt data transmission using the TLS protocol, preventing the risk of data theft or tampering.
Transport Protocol: HTTP/1.1 uses TCP as the transport layer protocol, while HTTP/2 and HTTP/3 use SPDY and QUIC respectively as transport layer protocols, designed to enhance performance and security. QUIC, based on UDP, offers better congestion control and connection establishment features compared to TCP.
| Browser | Initial Version with Implemented but Default Disabled | Support Date | Initial Version with Default Enabled | Date of Default Enabled Version | Remarks |
|---|---|---|---|---|---|
| Chrome | Stable Version (79) | December 2019 | 87 | Early versions implemented other drafts of QUIC | |
| Edge | Stable Version (79) | December 2019 | 87 | April 2020 | Edge 79 is the first version based on Chromium |
| Firefox | Stable Version (72.0.1) | January 2020 | 88 | April 2021 | |
| Safari | Stable Version (14.0) | September 2020 | 16.4 | March 2023 | Apple began testing HTTP/3 support for some Safari users starting from Safari 16.4 |
If unsure about browser support, directly visit https://quic.nginx.org. If the QUIC icon on the website turns colorful (as shown on the article cover), it indicates browser support for HTTP3.
| Server | Initial Version with Implemented but Default Disabled | Support Date | Initial Version with Default Enabled | Date of Default Enabled Version | Remarks |
|---|---|---|---|---|---|
| LiteSpeed Web Server | 6.0.2 | June 7, 2021 | 6.0.2 | June 7, 2021 | LiteSpeed Web Server version 6.0.2 became the first version to enable HTTP/3 by default. |
| Caddy Web Server | v2.6.0 | September 20, 2022 | v2.6.0 | September 20, 2022 | Caddy v2.6.0 enables HTTP/3 by default. |
| Nginx | 1.25.0 | May 23, 2023 | 1.25.0 | May 23, 2023 | Nginx started supporting HTTP/3 from version 1.25.0. A technology preview supporting HTTP/3 was released in 2020, followed by binary package releases supporting HTTP/3 in 2023. |
| Cloudflare | - | - | - | - | Cloudflare released a patch integrating the quiche HTTP/3 library into Nginx. |
| Microsoft IIS | - | - | - | - | Microsoft IIS natively supports HTTP/3 on Windows Server 2022/Windows 11. |
| HAProxy | 2.6 | May 31, 2022 | 2.6 | May 31, 2022 | HAProxy supports HTTP/3 over QUIC from version 2.6. |
nginxserver { listen 443 ssl; listen [::]:443 ssl; # Listen for HTTP3 listen 443 quic reuseport; listen [::]:443 quic reuseport; location / { add_header alt-svc 'h3=":443"; ma=2592000'; # Add HTTP3 response header ... } ... }
Then, reload the Nginx configuration to enable HTTP/3 support. In case of incompatibility, it will automatically degrade to HTTP/2 or HTTP/1.1.
bash# Test configuration
nginx -t
# Reload configuration
nginx -s reload
At this point, the server setup is complete.
If using Caddy, HTTP/3 support is enabled by default.
Next, you can use the following tools for testing, taking this site as an example:
Using testing websites: http3check.net or http3.wcode.net
Using Chrome browser developer tools.
Note: Using proxy tools may prevent the use of HTTP3, even in Direct mode.
To enable HTTP3, TUN mode must be used.
References: