Patent ID: 8606964

Claim:
A method comprising: receiving, at a route controller, demand information from a plurality of edge routers that direct requests from a client system to one of a plurality of cache servers, wherein each of the cache servers provides content to the client system in response to the requests; estimating an optimal request distribution based on the demand information using a bicriteria approximation algorithm, wherein initial programming states for the estimation are specified by (u, F, D, F s , D s , F exp , Fimp), where u is a current node, F is a vector representing an available facility for large capacity, D is a vector representing an outsourced large client, F s is an amount of cache server capacity offered to small clients, D s is a total demand of outsourced small clients, F exp is an index of a cache server being exported from a subtree, and F imp is an index of another cache server of another subtree that is being utilized; and providing each of the edge routers with anycast route information for the cache servers.