This pocket guide offers a clear and accessible introduction to HTTP/3, the latest version of the Hypertext Transfer Protocol, and QUIC, a new transport protocol designed to significantly enhance the speed, security, and reliability of internet connections. As successors to HTTP/2 and TCP, these protocols address longstanding issues in web performance and offer substantial improvements—especially for the applications and users that need them most.

Whether you're a web developer, a networking novice, or simply curious about how the internet works, this guide provides a straightforward and easy-to-follow explanation of these modern technologies. It’s not intended as a comprehensive reference—after all, the full set of RFCs that define HTTP/3 and QUIC is extensive, and you will not that level of detail to get started. Instead, The HTTP/3 Playbook focuses on practical understanding. You’ll learn why HTTP/3 and QUIC were developed, how they work, and how to deploy and test them effectively.

By the end, you’ll have a solid foundation to grasp these technologies, understand their real-world impact, and confidently deliver your own web services using HTTP/3.

You Will Learn:

• To understand the limitations of HTTP/2 and TCP, and why HTTP/3 and QUIC were developed to replace them
• The key features, mechanisms, and advantages of these protocols—including multiplexing, connection migration, encryption, and 0-RTT
• A step-by-step approach as to how requests and responses are handled differently under HTTP/3 compared to earlier versions
• How QUIC integrates TLS 1.3 to provide secure connections without added handshake delays
  

This Book is for:

Web developers and system administrators

When not writing and pentesting for Radically Open Security, working on smartmessages.net, or supporting 1CRM, Marcus Bointon is the maintainer of PHPMailer, the second-most forked PHP project on GitHub, and probably the world's most popular code for sending email. He's a contributor to many other open source projects, and wrote the HTML5 email address spec. He's an accomplished PHP & Laravel developer, security specialist, Linux sysadmin, and technical writer.

Marcus is a strong advocate of digital rights and privacy – especially GDPR! — and has been speaking at technical conferences around the world since 2006. He lives in the French alps where he skis and writes songs about web development with his wife, kids, cat, guitars, bikes, and far too many skis.