Patent ID: 7697557

Claim:
A method for managing content items stored in a content distribution network having a plurality of tiers, the method comprising: determining, at a first network node, a list of currently cached content items; creating a list of highest utility content items, the list of highest utility content items structured as a self-organizing hierarchy of rarity based upon a likelihood that users will request content items from the first network node, wherein the content items are respectively cached in the plurality of tiers based upon the likelihood that the users will access the content items, such that content items with high probability of being accessed are cached closer to a user, while rarely accessed content items are stored more centrally at a distant network store; comparing the list of highest utility content items to the list of currently cached content items; determining a ranked list of candidates for caching, the ranked list of candidates for caching comprising the content items if the list of highest utility content items that are not in the list of currently cached content items wherein the list of candidates for caching is ranked according to a utility measure of a probability that the selected content item will be accessed; and receiving from a second network node, at the first network node, a selected content item from the list of candidates for caching.