Voice Mail Integration

CUCM can integrate with Cisco Unity via either Skinny Client Control Protocol (SCCP) or Session Initiation Protocol (SIP).

Cisco Unity telephony integrations are configured with the Cisco Unity Telephony Integration Manager (UTIM).

In addition to the option of adding multiple clusters by adding additional integrations for each new CUCM cluster in Cisco Unity, CUCM supports Annex M.1, Message Tunneling for Q Signaling (Q.SIG), which allows administrators to enable Q.SIG on intercluster trunks (ICT) between CUCM clusters.

The phone system sends the following information with forwarded calls to the voice-mail system:

■ The extension of the called party

■ The extension of the calling party (for internal calls) or the phone number of the calling party (if it is an external call and the system uses caller ID)

■ The reason for the forward (the extension is busy, does not answer, or is set to forward all calls)

Cisco Unity uses this information to answer the call appropriately. A call forwarded from a subscriber phone to Cisco Unity is answered with the personal greeting of the subscriber. A call from a nonsubscriber is routed the opening greeting of the automated attendant (AA) server in Cisco Unity.

The Cisco Messaging Interface (CMI) is a CUCM service that should run on the publisher server if a Simplified Message Desk Interface (SMDI) integration to a third-party voice-mail system will be used. The CMI service is not used when integrating with Cisco Unity. Cisco Unity and CUCM support a digital IP-based integration that is much faster than using CMI integration.

The CMI service intercepts calls destined for voice mail and generates appropriate SMDI messages over RS-232 serial cables. The CMI service is compatible with any Media Gateway Control Protocol (MGCP) gateway that supports analog Foreign Exchange Station (FXS) or T1 channel associated signaling (CAS). The Cisco Catalyst 6500 WS-X6624 module and the standalone Cisco VG224 devices are two of only three gateways that support positive disconnect supervision and are therefore the only gateways currently recommended for use with the CMI service.

CUCM supports CMI integration with the following voice-mail systems:

■ Intuity Audix

■ Siemens PhoneMail

■ Centigram/BayPoint (OnePoint and NuPoint Messenger)

■ IBM Message Center

The Cisco VG248 is an SCCP gateway that supports 48 analog FXS ports through two amphenol (RJ-71) connectors and generates SMDI locally. The Cisco VG248 also supports positive disconnect supervision.

Voice-mail integration through the Cisco VG248 provides the following features and advantages:

■ Multiple SMDI links per CUCM server

■ SMDI failover capability

■ Independence from the location of the voice-mail system

The Cisco VG248 can also support two other serial protocols that are sometimes used for voice-mail integration: NEC Message Center Interface (MCI) and Ericsson MD110 proprietary protocol.

CUCM SCCP integration with Cisco Unity provides the following features:

■ Call forward to personal greeting

■ Call forward to busy greeting

■ Easy message access. A subscriber can retrieve messages without entering an extension identifier. Cisco Unity identifies a subscriber based on the extension from which the call originated. A password is normally required, but the subscriber can be configured without a password if desired.

■ Identified subscriber messaging. Cisco Unity automatically identifies a subscriber who leaves a message during a forwarded internal call. This feature is based on the extension from which the call originated (original calling party).

■ Message Waiting Indication (MWI). When a message is left for a subscriber, a red light is illuminated on the Cisco IP Phone. The directory number (DN) that has a voice-mail message also displays a mail icon next to the DN on the phone.

Call Routing to Cisco Unity

The following examples describe how calls are routed through CUCM to Unity.

Outside Calls

Figure 18-2 is an example of how a call is routed from an outside caller through CUCM to a Unity system. The following list annotates the numbers that are in Figure 18-2.

1. The outside caller dials a phone number from his cell phone. The phone number dialed is a direct inward dial (DID) number that belongs to a Unity subscriber.

2. The public switched telephone network routes the caller to the gateway. The gateway router forwards the digits to CUCM for processing. The number of digits forwarded is controlled by the inbound call-routing parameters in the gateway configuration. If an internal five-digit dial plan is deployed, only the last five digits are required.

3. CUCM performs digit analysis and routes the call to the appropriate Cisco IP Phone.

4. The telephone rings four times based on the default ring no answer duration. After four rings, the Call Forward No Answer (CFNA) setting is applied and the phone is sent to the voice-mail profile of the subscriber.

5. CUCM checks the voice-mail profile of the Cisco IP Phone and forwards the call to the Unity server handling the IP phone. Unity directs the call to the subscriber greeting.

6. The caller leaves a message, and Unity directs the call to the message store. In a Unified Messaging deployment, the message store (Microsoft Exchange or IBM Lotus Domino) is external from the Cisco Unity platform.

7. The message is stored in the subscriber message store.

8. Cisco Unity sends a code to CUCM to turn on the MWI light on the phone that has a new message.

9. CUCM instructs the phone to turn on the MWI light.

10. The MWI light is illuminated on the phone.

Figure 18-2 Outside Caller Call Flow

Figure 18-2 Outside Caller Call Flow

Planar Fitting

The correct calling privileges (calling search spaces [CSS]) are assigned to the voice-mail ports, gateways, phones, and MWI ports. Phone numbers are in partitions, whereas devices are assigned to CSSs.

Calling privileges (class of restriction) were covered in detail in Chapter 13, "Calling Privileges." The following calling privilege need to achieve the following:

■ The gateway should be able to reach the phones and voice-mail ports.

■ The phones should be able to reach the voice-mail ports but should not be able to dial the MWI On or MWI Off codes (extensions).

■ The voice-mail ports should be able to dial the MWI On and MWI Off extensions.

Subscriber Call Flow

A Cisco Unity subscriber is a person who has a user account on the Cisco Unity system. Each subscriber account has a Profile page that stores specific information about that subscriber, such as the extension, security code, recorded name, and the e-mail alias to send messages to. The following steps describe the call flow of a user checking a voice-mail message in Cisco Unity, as depicted in Figure 18-3:

1. The subscriber notices the MWI on his telephone and presses the Messages button on the phone to retrieve messages. CUCM receives the Messages button event from the IP phone.

2. CUCM directs the call with the caller ID information to the Cisco Unity system.

3. Cisco Unity receives the call and the extension of the telephone from the telephone system. Cisco Unity recognizes the extension from its list of subscribers. The subscriber is prompted to enter his password.

4. The user enters his password and chooses to listen to a new voice-mail message.

5. Cisco Unity accesses the subscriber's message store to retrieve the voice message when the subscriber chooses to listen to his messages.

6. The subscriber listens to the message. Unity offers a menu of actions to take with the message: save, delete, or forward. The subscriber presses the digit 3 to delete the message, and Cisco Unity verbally confirms the message is deleted. The subscriber then hangs up the phone.

7. Cisco Unity sends the subscriber's delete message command to the message store server. The message will be deleted or moved to the Deleted Items folder based on settings in the subscriber's account. Unity sends a message to CUCM to turn off the MWI code on the subscriber's IP phone.

8. CUCM sends an SCCP message to the IP phone instructing the phone to turn off the MWI.

9. The MWI light goes off on the phone.

Figure 18-3 Subscriber Call Flow

Figure 18-3 Subscriber Call Flow

Calls Forwarded to Voice Mail

Figure 18-4 illustrates the interworking of CUCM and Cisco Unity. Incoming calls forwarded to voice mail reach the voice-mail pilot number that is also assigned to the hunt pilot of the voice-mail hunt list. The voice-mail hunt list selects the voice-mail port, which terminates the incoming call.

Figure 18-4 Call Forward-to-Voice Mail Call Flow


MWI on Extension MWI off Extension

Voicemail Pilot

CUCM Hunt List

r \

Voice-Mail SCCP Port 1

Voice-Mail SCCP Port 2


Voice-Mail SCCP Port 3


Voice-Mail SCCP Port 4

Figure 18-4 Call Forward-to-Voice Mail Call Flow

Incoming Call \

Controls Terminating SCCP Port Plays Prompt Records Incoming Voice Calls MWI on Extension

SCCP Control with Unity tSP"

Cisco Unity

Controls Terminating SCCP Port Plays Prompt Records Incoming Voice Calls MWI on Extension

SCCP Control with Unity tSP"

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  • sophie
    Can a call be forwarded from cucm to an outside number then back to unity voice mail?
    11 months ago
  • tombur lightfoot
    Which signaling protocols can be used for integration between CUCM and CUC?
    4 months ago

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