Tag Archives: ssl

TLS Certificate Optimization: The Technical Details behind “No Browser Left Behind”

Overview Back in early December we announced our “no browser left behind” initiative to the world. Since then, we have served well over 500 billion SHA-1 certificates to visitors that otherwise would not have been able to communicate securely with our customers’ sites using HTTPS. All the while, we’ve continued to present newer SHA-2 certificates […]

SHA-1 Deprecation: No Browser Left Behind

After December 31, 2015, SSL certificates that use the SHA-1 hash algorithm for their signature will be declared technology non grata on the modern Internet. Google’s Chrome browser has already begun displaying a warning for SHA-1 based certs that expire after 2015. Other browsers are mirroring Google and, over the course of 2016, will begin […]

Happy 5th Birthday, CloudFlare!

CloudFlare customers recorded videos to celebrate our first five years Today is September 27, 2015. It’s a rare Super Blood Moon. And it’s also CloudFlare’s birthday. CloudFlare launched 5 years ago today. It was a Monday. While Michelle, Lee, and I had high expectations, we would never have imagined what’s happened since then. In the […]

How to build your own public key infrastructure

A major part of securing a network as geographically diverse as CloudFlare’s is protecting data as it travels between datacenters. Customer data and logs are important to protect but so is all the control data that our applications use to communicate with each other. For example, our application servers need to securely communicate with our […]

iOS Developers — Migrate to iOS 9 with CloudFlare

Thousands of developers use CloudFlare to accelerate and secure the backend of their mobile applications and websites. This week is Apple’s Worldwide Developers Conference (WWDC), where thousands of Apple developers come to San Francisco to talk, learn and share best practices for developing software for Apple platforms. New announcements from Apple this week make CloudFlare […]

Logjam: the latest TLS vulnerability explained

Yesterday, a group from INRIA, Microsoft Research, Johns Hopkins, the University of Michigan, and the University of Pennsylvania published a deep analysis of the Diffie-Hellman algorithm as used in TLS and other protocols. This analysis included a novel downgrade attack against the TLS protocol itself called Logjam, which exploits EXPORT cryptography (just like FREAK). First, […]

Why secure systems require random numbers

(Image Copyright (c) Walt Disney) If you’ve been following recent news about technical spying by the US National Security Agency and the UK’s Government Communications Headquarters you may have come across a claim that the NSA was involved in weakening a random number generator. The obvious question to ask is… why mess with random number […]

Staying on top of TLS attacks

CloudFlare makes extensive use of TLS connections throughout our service which makes staying on top of the latest news about security problems with TLS a priority. We use TLS both externally and internally and different uses of TLS have different constraints. Broadly there are three ways we use TLS: to handle HTTPS connections from web […]

What We Just Did to Make SSL Even Faster

A little over a month ago, we published a couple of blog posts about how we were making SSL faster. Specifically, we enabled OCSP stapling across our network. In brief, when you visit a page over HTTPS, your browser checks to see if the SSL certificate is still valid via a protocol called OCSP. Those […]