System and method for discovering information objects and information object repositories in computer networks
An address of an information object repository that should service a client request for an information object is returned in response to a request therefor. The address of the information object repository which is returned is selected according to specified performance metrics regardless of whether or not the information object repository maintains a local copy of the information object that is the client request. In some cases, the address of the information object repository is further selected according to an address of a client making the client request. Further, the address of the information object repository is selected from a number of addresses of information object repositories. The specified performance metrics may include one or more of an average delay from the information object repository to the client, average processing delays at the information object repository, reliability of a path from the information object repository to the client, available bandwidth in said path, and loads on the information object repository. In some cases, the information object repository may be instructed to obtain a copy of the information object after the address of the information object repository is returned in response to the request therefore.
1. A communication protocol, comprising messages passed between Web routers over a reliable transmission protocol used for inter-Web router communication, said messages (i) conveying mappings of client address ranges to addresses of Web caches and redirecting Web routers by specifying best distances known from individual ones of the Web caches or the redirecting Web routers to specific ones of the client address ranges, and (ii) organized as (a) routing updates having information needed for updating of minimum-hop distances to redirecting Web routers, (b) lists of distances from the Web caches to destinations, and (c) lists of distance from the redirecting Web routers to said destinations, wherein said destinations include one or more Web cache records, each comprising (a) addresses of specified ones of the Web caches or a content server that can serve specified ones of the client address ranges, (b) best distances from the specified ones of the Web caches or the content server to the specified ones of the client address ranges, and (c) addresses of those of the Web routers co-located with the specified ones of the Web caches or the content server.
2. The communication protocol of claim 1 , wherein the routing updates include one or more of distances to some or all of the Web routers, distances and second-to-last hops in the paths to some or all of the Web routers, entire minimum-hop paths to some or all of the Web routers, identifiers and lengths of virtual links defined between those of the Web routers that form part of a min-hop path to a first one of the Web routers, and identifiers and lengths of virtual links defined between those of the Web routers that form part of a virtual topology of Web routers defining an overlay network.
3. The communication protocol of claim 1 , wherein said destinations include the client address ranges.