Abstract: Storage locations, such as voice mailboxes are addressed on a plurality of widely distributed host systems, connect via a network, by defining logical domains Bach of which may include storage locations on more than one host system. The domains are defined by address tables which indicate which host systems provide ranges of address locations. Transfer of data between domains is simplified by the use of translation tables. One type of translation table is an alias table which has entries containing a range in the originating domain, a new domain and a starting point for a range in the new domain, thus defining a one-to-one correspondence between the ranges in the two domains. Another translation table is a gateway table which defines a gateway to a new domain when an input address has characteristics matching a prefix, number of digits, or both, of an entry in the gateway table.

Abstract: The present invention provides a distributed architecture that includes multiple voice processing unit each designated as a home unit for a subscriber's messages. An incoming call is preferentially switched to the home VPU by a digital switching system under the control of a master control unit. If a master control unit determines that all lines to the home unit are busy or the home unit is otherwise unavailable, the master unit causes the digital system to switch the call to another or remote voice processing unit. The remote unit then handles the call by either locally storing a message or retrieving a message from the home unit storage over an internal message bus.