Patent ID: 8219645

Claim:
A method to cache content objects in a content delivery network (CDN) according to an arrangement of using different parent caches for different URIs, the method comprising: receiving a first universal resource indicator (URI) at a cache of an edge server in a first points of presence (POP), wherein the first URI specifies a first content object; determining that the cache does not hold the first content object; analyzing the first URI to determine a first hierarchical tree of caches, the first hierarchical tree of caches having a plurality of levels of caches to successively receive content-object requests upon cache misses at previous levels, the first hierarchical tree of caches comprising the first parent cache; requesting the first content object from the first parent cache in a second POP; receiving a second URI at the cache of the edge server in the first POP, wherein the second URI specifies a second content object; determining that the cache does not hold the second content object; analyzing the second URI to determine a second hierarchical tree of caches, the second hierarchical tree of caches having a plurality of levels of caches to successively receive content-object requests upon cache misses at previous levels, the second hierarchical tree of caches comprising the second parent cache different from the first parent cache, wherein the second parent cache is in a third POP; and requesting the content object from the second parent cache.