Patent ID: 8135831

Claim:
A cache data structure implemented on a non-transitory, computer-readable medium, comprising: a hash array comprising one or more index elements, each index element comprising a host tree pointer and a hash key derived from a stored URL, wherein hashed host portions of at least two different URLs correspond to the same index element, wherein the same index element comprises a pointer to a combined host tree and age list; and wherein the combined host tree and age list comprises one or more tree nodes, wherein each tree node comprises URL data representing a specified URL and a category code corresponding to the URL data, and wherein each tree node comprises a next node pointer referring to a previous node, the next node comprising an age older than the previous node; and one or more host trees depending from said host tree pointers of the index elements of the hash array, each host tree comprising one or more tree nodes each holding URL data representing stored URLs and associated category codes.