MirrorBrain is a Download Redirector and generates cryptohashes, Metalinks, and even Torrents
MirrorBrain is an open source framework to run a content delivery network using mirror servers. It solves a challenge that many popular open source projects face - a flood of download requests, often magnitudes more than any single site could practically handle. Some very popular Open Source projects rely on MirrorBrain.
The central (and probably the most obvious) part is a "download redirector" which automatically redirects requests from web browsers or download programs to a mirror server near them.
For mirror choice and load-balancing for the mirrors, MirrorBrain uses geolocation and global routing data. The selection algorithm can be finely tuned, but is designed to have sensible defaults and work mostly automatically. In addition to network topography and country, the approximated geographical distance of mirrors is also taken into account. Mirror servers are monitored and scanned for files.
Furthermore, MirrorBrain can automatically keep cryptohashes of all files and can serve these on request. It can even generate Metalinks (RFC5854) and Torrents in realtime. (The Torrents are uniquely useful in that they contain webseeds - webseeds that work, specific to the client who requested them!)
How much traffic can MirrorBrain handle? Lots of, and you don't need a room full of servers. Let's look at an example: handling all downloads of OpenOffice.org, a busy site, could be called boring. A simple 512MB box can do this. Handling all openSUSE.org traffic (20-40 millions hits per day) is still relaxed (commodity hardware, server load: zero point something). That is comparable to all downloads from Apple's App Store worldwide (200 per second, as reported in autumn 2010). Do you need more?
See who uses MirrorBrain. Read the list of features. Contribute to MirrorBrain, or help with funding or hardware.
MirrorBrain is fully Open Source and free to use by anyone. It is licensed under GPL, with the exception of three Apache modules which are available under the terms of the Apache license, which basically means that you are free to get and use it for commercial and non-commercial purposes.
If you would like to get help with MirrorBrain, get in contact. Its author knows it inside out, can push the boundaries and maybe deliver the solution you want.