Technical deep dives, product updates, and insights from the teams that are helping to build a better Internet.
Visit blog.cloudflare.com → RSS feedOn Hacker News Jun 2011 – Nov 2026
Networking & Internet 106Security & Privacy 101Infrastructure & DevOps 77Web & Frontend 75Systems & Performance 64Software Engineering 53
When strikes hit Yandex data centers, many assumed Russian bot operations went dark. Cloudflare data reveals that while search crawling stopped, malicious bots simply migrated to other networks.
So what happened at all of those working group meetings, specification documents, and side events in 2022? What are implementers and deployers of the web’s protocol doing? And what’s coming next?
Today CenturyLink/Level(3), a major ISP and Internet bandwidth provider, experienced a significant outage that impacted some of Cloudflare’s customers as well as a significant number of other services and providers across the Internet.
Today CloudFlare is introducing HTTP/2 support for all customers using SSL/TLS connections, while still supporting SPDY. There is no need to make a decision between SPDY or HTTP/2.
A recent blog post posed the question Why do we use the Linux kernel's TCP stack?. It triggered a very interesting discussion on Hacker News.
As was mentioned in the original 1.1.1.1 blog post, our policy is to never write client IP addresses to disk and wipe all logs within 24 hours. Still some folks might not want to reveal their IP address to the resolver at all. This is why we are launching a Tor hidden service for our resolver.
Yesterday I posted a post mortem on an outage we had Saturday. The outage was caused when we applied an overly aggressive rate limit to traffic on our network while battling a determined DDoS attacker.
We're excited to announce a contribution to improving privacy for everyone on the Internet. Encrypted Client Hello, a new standard that prevents networks from snooping on which websites a user is visiting, is now available on all Cloudflare plans.
Introducing Spectrum: a new Cloudflare feature that brings DDoS protection, load balancing, and content acceleration to any TCP-based protocol.Today we are releasing Spectrum.
We announced support for HTTP/3, the successor to HTTP/2, during Cloudflare’s birthday week last year. Our goal is and has always been to help build a better Internet. Even though HTTP/3 is still in draft status, we've seen a lot of interest from our users.
I was asked to debug another weird issue on our network. Apparently every now and then a connection going through CloudFlare would time out with 522 HTTP error.
A discussion about IP blocking: why we see it, what it is, what it does, who it affects, and why it’s such a problematic way to address content online.
On Wednesday of last week, details of the Shellshock bash bug emerged. This bug started a scramble to patch computers, servers, routers, firewalls, and other computing appliances using vulnerable versions of bash.
On 4 October 2023, Cloudflare experienced DNS resolution problems. Some users may have received SERVFAIL DNS responses to valid queries. In this blog, we’re going to talk about what the failure was, why it occurred, and what we’re doing to make sure this doesn’t happen again
On Monday we mitigated a large DDoS that targeted one of our customers. The attack peaked just shy of 400Gbps. We've seen a handful of other attacks at this scale, but this is the largest attack we've seen that uses NTP amplification.
Cloudflare is launching an experiment with Chrome to evaluate fast, scalable, and quantum-ready Merkle Tree Certificates, all without degrading performance or changing WebPKI trust relationships.
We are announcing Cloudflare Calls, a new product that lets developers build real-time audio and video apps
The practice of HTTPS interception continues to be commonplace on the Internet. This blog post discusses types of monster-in-the-middle devices and software, and how to detect them.
We’re announcing the closed beta of a self-serve Cloudflare OHTTP Gateway. We’re also renaming our Privacy Gateway to Cloudflare OHTTP Relay to better distinguish the two products.
Some time ago we discovered that certain very slow downloads were getting abruptly terminated and began investigating whether that was a client (i.e. web browser) or server (i.e. us) problem.
The “HTTP/2 Rapid Reset” attack exploits a weakness in the HTTP/2 protocol to generate enormous, hyper-volumetric DDoS attacks. Cloudflare has mitigated a barrage of these attacks in recent months, including an attack three times larger than any previous attack we’ve observed
Zone setting changes used to rebuild entire DNS zones, even ones with tens of millions of records. Here is how we built a planner that picks the smallest safe build, cutting full builds by 40%, peak memory by 85%, and halving build delay.
Over the few last hours, a dozen news stories have broken about how an attacker attempted (and perhaps managed) to steal cryptocurrencies using a BGP leak.
Often programmers have assumptions that turn out, to their surprise, to be invalid. From my experience this happens a lot. Every API, technology or system can be abused beyond its limits and break in a miserable way
Internally our DDoS mitigation team is sometimes called "the packet droppers". When other teams build exciting products to do smart things with the traffic that passed through our network, we take joy in discovering novel ways of discarding it.
Two summers ago, with a seemed-big-at-the-time network of 28 datacenters, not long after introducing Medellin, CloudFlare introduced support for WebSockets, initially for our Enterprise customers.
If I navigate to https://blog.cloudflare.com/, my browser will connect to a remote TCP address from the local IP address assigned to my machine, and a randomly chosen local TCP port. What happens if I then decide to head to another site?
On Friday, we announced DNS analytics for all Cloudflare customers. Because of our scale –– by the time you’ve finished reading this, Cloudflare DNS will have handled millions of DNS queries –– we had to be creative in our implementation.
In two previous posts we've discussed how to receive 1M UDP packets per second and how to reduce the round trip time. We did the experiments on Linux and the performance was very good considering it's a general purpose operating system.
I'm pleased to announce that CloudFlare now supports WebSockets. The ability to protect and accelerate WebSockets has been one of our most requested features.