US Patent 8745221 Dynamic request rerouting

A point of presence includes edge servers having IP addresses and storing content, a switch/router that receives and forwards requests for content to the edge servers, a health monitoring server that gathers health information from the edge servers, and a dynamic request rerouting (DRR) server. The DRR server is connected with each of the edge servers. If the DRR server obtains a determination that one of the edge servers is down, it advertises a route including the IP address of the down edge server to the switch/router. The switch/router forwards a request for content, originally addressed to the down server, to the DRR server. The DRR server forwards the request to a working server that stores the content. The working server sends the content to the DRR server, the DRR server forwards the content back to the switch/router, and the switch/router responds to the original request with the content.