Patent ID: 7313598

Claim:
A method of partially replicating directory information from a master directory server to one or more associated slave directory servers, the method comprising the computer-implemented steps of: receiving, at a network routing device configured to operate as a slave directory server used by one or more application programs that use master directory information, a request that includes one or more filter criteria that define a subset of a sub-tree of the master directory information for replication, wherein the master directory information is stored at a master directory server, determining, based at least in part on processing power of the slave directory server, how often the slave directory server receives the subset of the sub-tree of the master directory information; if a network connection between the master directory server and the network routing device is functioning, then at the network routing device: sending to the master directory server, using a directory access protocol, a directory access protocol request comprising a query that includes the one or more filter criteria; receiving the subset of the sub-tree of the master directory information from the master directory server in a directory access protocol response; and storing only the subset of the sub-tree of the master directory information in the slave directory server; and if the network connection between the master directory server and the network routing device is not functioning, then at the network routing device: if the subset of the sub-tree of the master directory information is stored at the slave directory server, then serving from the slave directory server only the subset, and if the subset of the sub-tree of the master directory information is not stored at the slave directory server, then directing the query to a different slave directory server on which the subset is stored.