The biggest win from CDNs like CloudFlare as compared to just using properly-configured in-house servers is global distribution. Downloading a JS file from a se

The biggest win from CDNs like CloudFlare as compared to just using properly-configured in-house servers is global distribution. Downloading a JS file from a server a mile from your house is a lot faster (often by hundreds of milliseconds) than downloading one from hundreds or thousands of miles away, and CloudFlare probably has a server a mile from your house. And it's prohibitively expensive to build your own global network that compares to CloudFlare's scale unless you're a very large company like Apple. As for dynamic page caching, CloudFlare offers a service called Railgun that only sends the diffs of a page when it's been changed, rather than the full page, and then re-hydrates it at the edge of their network before handing it off to end-users. Theoretically this would reduce network time by sending less traffic inside the network. I've never personally used it so I can't vouch for it, but it sounds neat.