The Administration of a Cisco CallManager
Other points to bear in mind when looking at the Unity solution is the scalability
as well as the integration into legacy PBXs. Cisco supports certain legacy
PBXs (Nortel Meridian 1, for example) allowing you a smooth transition to IP
telephony. A listing of those currently supported can once again be found on the
Cisco Web site.
WARNING
If you’re looking to migrate from voice mail only to unified messaging,
remember to make sure the hardware requirements for running unified
messaging is met. Even though it is only a software upgrade, the
requirements are not the same.