There is one PBX connected to a VoIP Gateway in San Francisco. The VoIP Gateway is connected to two Voicemail & Fax Servers, both in New York. One of the PBXes is displayed on a shaded background, indicating this is a new Voicemail & Fax Server. Both Voicemail & Fax Servers are shown connecting to the Infrastructure Tier, consisting of the Oracle Collaboration Suite Database and Oracle Internet Directory.