How would you build a video streaming service without a CDN? A CDN doesn't just solve the content distribution problem - it also solves the bandwidth problem.
With a 1Gig connection you can only serve ~45 concurrents streaming 1080p. If you wanted to support more than 45 concurrents, you would need
1. To distribute content to separate instances
2. A routing infrastructure to reliably route connections to that content.
And then, congrats, you have just built your own CDN - albeit in one datacenter. If you don't want your users on the other side of the country constantly complaining that your site is slow compared to Vimeo, you would have to build it on the other side as well.
If you believe your hodgepodge CDN is going to be much cheaper than Cloudfront (on the order of 1 Euro/month, where you could support it on ~1.5M views/month), then you should probably skip the whole video sharing nonsense, and get rich becoming a CDN provider :)
My point is, you don't need an expensive global CDN if your end goal is to optimize for ad-revenue within the U.S market. I don't know why you stuck on the CDN, and it sounds like you are using it as a hammer to achieve scalability.
I'm stuck on the CDN because you need something like a CDN to serve any meaningful number of concurrents. The numbers I quoted for cloudfront were for the US.
If you believe otherwise, please enlighten me on how you can build a HD video streaming service for 100 concurrents without a CDN. Like I mentioned, on a 1GbE connection, you can serve a theoretical max of 45 users on one node. Where do you go from there without something that looks like CDN?
With a 1Gig connection you can only serve ~45 concurrents streaming 1080p. If you wanted to support more than 45 concurrents, you would need
1. To distribute content to separate instances
2. A routing infrastructure to reliably route connections to that content.
And then, congrats, you have just built your own CDN - albeit in one datacenter. If you don't want your users on the other side of the country constantly complaining that your site is slow compared to Vimeo, you would have to build it on the other side as well.
If you believe your hodgepodge CDN is going to be much cheaper than Cloudfront (on the order of 1 Euro/month, where you could support it on ~1.5M views/month), then you should probably skip the whole video sharing nonsense, and get rich becoming a CDN provider :)