Patent ID: 6970944

Claim:
A method for routing requests for data from a client between a plurality of routers in a network, the method comprising: at a router in a replica routing system: receiving a client request for data; comparing originating address information in the received client request to coverage zone information associated with i) the router that received the request and ii) a hierarchy of routers that are the router's progeny, the coverage zone information being stored in a database associated with the router that received the request, the coverage zone information including a first set of coverage zone information and a second set of coverage zone information for respective a first type coverage zone and a second type coverage zone, the first set of coverage zone information including a restrictive set of addresses associated with requests for which corresponding routers in the first type coverage zone believe that they would be at least as good as any other router in the hierarchy at servicing the requests, the second set of coverage zone information including a larger set of addresses than that associated with the first set of coverage zone information, routers in the second type coverage zone being able to service the requests but for which the routers do not know whether they are an optimal router for servicing the requests; and based on the comparing: forwarding, if the router is not within the first type coverage zone, the client request message to a successive router within the first type coverage zone; and forwarding, if the originating address information corresponds to a router in the second type of coverage zone, the client request message to a successive router within the second type coverage zone.