You might use Cisco IPC Express as a standalone system, or you might interconnect multiple Cisco CME sites. You might also use a centralized Cisco Unity for voice mail. For these types of networks, you have to configure not only the Cisco IPC Express system itself, but also the interconnectivity between the sites.
The topics of site interconnection and examples of the salient aspects of Cisco IPC Express system configuration were covered in other chapters:
Security Best Practices for Cisco CME