Patent ID: 7640340

Claim:
An apparatus for managing leased network addresses for a plurality of networks using overlapping address spaces, comprising: a network interface that is coupled to one or more intermediate devices connected to the plurality of networks; a processor; and one or more stored sequences of instructions which, when executed by the processor, cause performing: storing a plurality of banks of addresses corresponding to the plurality of networks, wherein each bank includes a pool of available addresses and a data structure of leased addresses, wherein at least one particular set of one or more network addresses is included in more than one bank of the plurality of banks; receiving a request for a network address for a host on a first network of the plurality of networks from a relay agent on an intermediate device connected to the first network, the request including a qualifier associated with the first network by the relay agent; based on the qualifier, selecting a first bank of addresses from the plurality of banks; identifying a first network address from the first bank of addresses based at least in part on the request; and sending to the relay agent a response for the host, the response indicating the first network address and the qualifier.