2 responses to “CDN”

  1. I would also recommend CloudFlare. CloudFlare is free (you can pay for additional features) and works at the DNS level: you re-route your domains through CloudFlare, and it will cache everything on its 14 or so data centres spread around the world, and serve content from wherever it’s nearest to the caller.

    As a bonus, it includes a way lot of security checks. So much, in fact, that popular websites constantly under DDoS attack (like Spamhaus, which helps fighting the war against spam — and, as such, are often victims of attacks to bring it down) are all behind CloudFlare’s servers. I have tested the efficacy of this extra level of protection once a few websites of mine were under attack, and it works flawlessly.

    50% bandwidth savings are common on average websites, but this depends a lot upon what kind of content you have and how your (internal) caching system is helping. W3 Total Cache works beautifully with CloudFlare, and, for instance, it can delegate minification to CloudFlare instead of using its own algorithms (it means less CPU consumption on newly published content). CloudFlare also provides a “always on” feature — you will get a snapshot of your website’s homepage if your server is down — and, for premium users, it can pre-load all your content, turned static, so your visitors will continue to navigate without noticing that your website is down.

    Technically it’s not really a CDN, since it acts as a reverse proxy/cache, and not really as a remote location for you to store your content. But from the perspective of the end-user, it serves exactly the same purpose. And, of course, it beats everything in terms of pricing 🙂

    • We tried CloudFlare but it has many limitations. For example, you cannot upload files greater than 100MB. They ask you use a different domain to access site for larger upload or use ftp-like methods.

      Many backend apps were needing changes because they depend on visitor-IP for geotargeting, default language and currency, etc.

      Some ecommerce apps who stores credit-card were also running into PCI compliance issues.

      CloudFlare is good for typical “content” sites. If you have e-commerce, or doing something with visitor IP address, you will be up for plenty of headache!

      Even if you use CloudFlare, you will need a traditional CDN specially if your site is up. They will expect you to upgrade to much higher plan or simply use external CDN like Amazon Cloudfront. Here is one interesting discussion related to this – http://phoboslab.org/log/2013/02/how-much-traffic-is-too-much-traffic-for-cloudflare

      That being said, cloudflare’s idea is nice and we are working on creating a private cloudflare like CDN for our clients where multiple nginx will be used as reverse proxy + amazon route53 latency based routing + etc. Of-course, with this setup also we need to live with some headache but we can atleast solve few problems on our own thanks to Nginx in front-line.