HTTP/3 inspection on Cloudflare Gateway

Today, we’re excited to announce upcoming support for HTTP/3 inspection through Cloudflare Gateway, our comprehensive secure web gateway. HTTP/3 currently powers 25% of the Internet and delivers a faster browsing experience, without compromising security. Until now, administrators seeking to filter and inspect HTTP/3-enabled websites or APIs needed to either compromise on performance by falling back to HTTP/2 or lose visibility by bypassing inspection. With HTTP/3 support in Cloudflare Gateway, you can have full visibility on all traffic and provide the fastest browsing experience for your users.

HTTP is one of the oldest technologies that powers the Internet. All the way back in 1996, security and performance were afterthoughts and encryption was left to the transport layer to manage. This model doesn’t scale to the performance needs of the modern Internet and has led to HTTP being upgraded to HTTP/2 and now HTTP/3.

HTTP/3 accelerates browsing activity by using QUIC, a modern transport protocol that is always encrypted by default. This delivers faster performance by reducing round-trips between the user and the web server and is more performant for users with unreliable connections. For further information about HTTP/3’s performance advantages take a look at our previous blog here.

Cloudflare’s mission is to help build a better Internet. We see HTTP/3 as an important building block to make the Internet faster and more secure. We worked closely with the IETF to iterate on the HTTP/3 and QUIC standards documents. These efforts combined with progress made by popular browsers like Chrome and Firefox to enable QUIC by default have translated into HTTP/3 now being used by over 25% of all websites and for an even more thorough analysis.

We’ve advocated for HTTP/3 extensively over the past few years. We first introduced support for the underlying transport layer QUIC in September 2018 and then from there worked to introduce HTTP/3 support for our reverse proxy services the following year in September of 2019. Since then our efforts haven’t slowed down and today we support the latest revision of HTTP/3, using the final “h3” identifier matching RFC 9114.

But while there are many advantages to HTTP/3, its introduction has created deployment complexity and security tradeoffs for administrators seeking to filter and inspect HTTP traffic on their networks. HTTP/3 offers familiar HTTP request and response semantics, but the use of QUIC changes how it looks and behaves "on the wire". Since QUIC runs atop UDP, it  is architecturally distinct from legacy TCP-based protocols and has poor support from legacy secure web gateways. The combination of these two factors has made it challenging for administrators to keep up with the evolving technological landscape while maintaining the users’ performance expectations and ensuring visibility and control over Internet traffic.

Without proper secure web gateway support for HTTP/3, administrators have needed to choose whether to compromise on security and/or performance for their users. Security tradeoffs include not inspecting UDP traffic, or even worse forgoing critical security capabilities such as inline anti-virus scanning, data-loss prevention, browser isolation and/or traffic logging. Naturally, for any security conscious organization discarding security and visibility is not an acceptable approach and this has led administrators to proactively disable HTTP/3 on their end user devices. This introduces deployment complexity and sacrifices performance as it requires disabling QUIC-support within the users web browsers.

Once support for HTTP/3 inspection is available for select browsers later this year, you’ll be able to enable HTTP/3 inspection through the dashboard. Once logged into the Zero Trust dashboard you will need to toggle on proxying, click the box for UDP traffic, and enable TLS decryption under Settings > Network > Firewall. Once these settings have been enabled; AV-scanning, remote browser isolation, DLP, and HTTP filtering can be applied via HTTP policies to all of your organization’s proxied HTTP traffic.

Administrators will no longer need to make security tradeoffs based on the evolving technological landscape and can focus on protecting their organization and teams. We’ll reach out to all Cloudflare One customers once HTTP/3 inspection is available and are excited to simplify secure web gateway deployments for administrators.

HTTP/3 traffic inspection will be available to all administrators of all plan types; if you have not signed up already click here to get started.