CoDeeN is a proxy server system created at Princeton University in 2003 and deployed for general use on PlanetLab.It operates as per the following: Users set their internet caches to a nearby high bandwidth proxy that participates in the system. Requests to that proxy are then forwarded to an appropriate member of the system that is in charge of the file (should be caching it) and that has sent recent updates showing that it is still alive.