[mixedbit]

I'm pondering using standard CDNs for serving bandwidth intensive payloads, but I have some doubts whether this is a right technical decision. I did not find any general purpose CDN that would explicitly encourage the use of their product for large files nor a CDN that would disclose any information how large payloads are handled by their infrastructure.

The primary use case for CDN is latency reduction for serving small files (CSS, JS, images) and such traffic has different characteristic and requires different optimizations than high-throughput traffic. I worry how long large files are going to be cached by CDN PoPs. PoPs can't certainly cache everything forever and they can be more eager to remove large files and in such case CDN will be reducing performance by adding an additional HTTP level hop to the origin server (and likely a few IP level hops). My other worry is that PoPs can deploy DoS detection heuristic that are tuned for standard web pages and a bandwidth intensive page may trigger the rules and have the traffic throttled. Such throttling is something that I've occasionally observed while testing CloudFlare with large files, but I'm not sure what was the cause, CloudFlare monitoring tools did not report anything unusual.

[mrkurt]

Most CDNs started by offering video, not necessarily latency reduction but a ton of bandwidth. Many of them allow you to upload videos directly.

Check out cachefly.com for instance.