Patent ID: 7369648

Claim:
A system for providing PBX-integrated unified messaging services including voice messaging, fax messaging, and e-mail messaging on a wide-area network, comprising: one or more corporate communication platforms, each of said one or more corporate communication platforms coupled to a switched backbone, integrated with a PBX via a PBX interface, and comprising a slave message mailbox cache; and a plurality of system communication platforms coupled to said switched backbone, wherein one such system communication platform comprises a master communication platform configured to update a subscriber database in each of said plurality of system communication platforms to reflect changes to a global subscriber database when said master communication platform determines said global subscriber database has changed, and wherein one such system communication platform comprises a master message mailbox, each of said slave message mailbox cache and said master message mailbox configured to store a plurality of message types, said message types comprising email, voicemail, and fax, wherein said slave message mailbox cache is bi-directionally synchronized in real-time with said master message mailbox such that each change to said slave message mailbox cache is reported immediately to said one such system communication platform, each change to a message in said master message mailbox that is associated with a corporate communication platform comprising said slave message mailbox cache is reported immediately to said corporate communication platform comprising said slave message mailbox cache, and each change to a message in said master message mailbox that is not associated with said corporate communication platform comprising said slave message mailbox cache is not reported to the corporate communication platform comprising said slave message mailbox cache, each of said one or more corporate communication platforms assigned to one of said plurality of system communication platforms, each of said plurality of system communication platforms assigned to zero or more of said one or more corporate communication platforms.