A company which as experienced a great increase in usage over the last years, but which is unknown to non IT specialists. It's a content delivery network. It helps internet sites to load webpages faster. Cloudflare also prevents Distributed Denial Of Service.

The principle is easy, from the website user perspective, it's like your site is hosted by CloudFlare. The user never know the real ip of your Server, and dialogs only with a CloudFlare machine. Your server only dialog with CloudFlare machines (so you can block all other traffic easily and fast if your ip is somehow discovered). For the technical details : They have a bunch of worldwide distributed ips, and behind each of these ips hides a reverse proxy (a customized nginx server using consistency hashing).

They are a very small structure of less than 50 people. And have scaled very rapidly using opensource and big data technologies. They analyse and filter all the data that goes through them, i.e. all the data of CloudFlare websites. They act as a SSL endpoint. This mean you don't have to own a ssl certificate. But it also means they decrypt all the traffic, and possibly inject anything. Oh, by the way, their terms of use, grant them ownership of everything that pass through them...

But they have very attractive pricing starting gratis. Lots of users, lots of traffic, very easy to use. An other player which is centralizing Internet. This is Man in The Middle 2.0.

CloudFlare

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