Information Technology Reference
In-Depth Information
Cisco Unity Connection and CUCM Interaction
Outside of CUCM Business Edition, where CUCM and Unity Connection reside on a sin-
gle server, Cisco Unity Connection operates independently from CUCM. As a matter of
fact, you can run Cisco Unity Connection as a voicemail server for other non-Cisco VoIP
deployments or even PBX systems; it is not tied to only the CUCM product. Because of
this, there is not a simple “click this button in CUCM to magically integrate with Cisco
Unity Connection.” Instead, you set up Cisco Unity Connection as an outside system that
CUCM can communicate with using the SCCP or SIP signaling protocols. Figure 2-7 illus-
trates this connection.
PSTN
Digital or
Analog Audio
1
Voice
Router
V
Analog PSTN
Phone
CUCM
Server
3
V
2
Switch
Cisco IP Phone
Unity Connection Server
Figure 2-7
CUCM and Cisco Unity Connection Communication
Although you can dive into much detail regarding the communication between CUCM
and Unity Connection, let's start by breaking down the high-level diagram shown in
Figure 2-7:
1.
An incoming call from the PSTN arrives at the voice router. The dial-plan on the voice
router causes it to route the incoming call to the CUCM server.
2.
CUCM receives the call and directs it to the appropriate IP phone (using SCCP or
SIP). If someone does not answer the IP phone or diverts the call to voicemail,
CUCM forwards the call to the preconfigured extension that reaches the Unity Con-
nection server.
Key
To p i c
