Integration with Cisco Unified Communications Manager

Cisco Unified Communications Manager, Cisco Unified Communications Manager Express, and SIP proxy servers use network connections that carry all communication to and from Cisco Unity Connection. Figure 11-1 shows the network connections used in an integration with Cisco Unified CM.

Figure 11-1 Connections for an Integration with Cisco Unified Communications Manager

See the “Integrating with Cisco Unified Communications Manager (Using SCCP or SIP)” section for additional information.

Digital Integration with Digital PIMG Units

The phone system sends call information, MWI requests, and voice connections through the digital lines, which connect the phone system to the PIMG units (media gateways). The PIMG units communicate with the Cisco Unity Connection server through the LAN or WAN using Session Initiation Protocol (SIP). Figure 11-2 shows the connections used in a digital integration using digital PIMG units.

Figure 11-2 Connections for a Digital Integration Using Digital PIMG Units

DTMF Integration with Analog PIMG Units

The phone system sends call information, MWI requests, and voice connections through the analog lines, which connect the phone system to the PIMG units (media gateways). The PIMG units communicate with the Cisco Unity Connection server through the LAN or WAN using Session Initiation Protocol (SIP). Figure 11-3 shows the connections for a DTMF integration using analog PIMG units.

Figure 11-3 Connections for a DTMF Integration Using Analog PIMG Units

Serial (SMDI, MCI, or MD-110) Integration with Analog PIMG Units

The phone system sends call information and MWI requests through the data link, which is an RS-232 serial cable that connects the phone system and the master PIMG unit (media gateways). Voice connections are sent through the analog lines between the phone system and the PIMG units. The PIMG units communicate with the Cisco Unity Connection server through the LAN or WAN using Session Initialization Protocol (SIP). Figure 11-4 shows the connections for a serial integration using analog PIMG units.

Figure 11-4 Connections for a Serial (SMDI, MCI, or MD-110) Integration Using Analog PIMG Units

Note When you use multiple PIMG units, one PIMG unit must be designated the master PIMG unit, which is connected to the serial cable from the phone system. It is not possible to “daisy chain” the serial ports on the PIMG units.

You can add a secondary master PIMG unit to an integration. For details, see the “Adding a Secondary Master PIMG Unit” chapter of the PIMG Integration Guide for Cisco Unity Connection Release 10.x, at http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/connection/10x/integration/guide/pimg/guide/cucintpimg/cucintpimg300.html.

TIMG Serial (SMDI, MCI, or MD-10) Integration

The TIMG integration uses one or more TIMG units between circuit-switched phone systems and IP networks. On the circuit-switched phone system side, there is a T1-CAS interface. On the IP side, there is a SIP interface, which is how Cisco Unity Connection communicates with the TIMG units. To Unity Connection, the integration is essentially a SIP integration. Unity Connection communicates with the TIMG units over the IP network using SIP and RTP protocols. The TIMG units communicate with the circuit-switched phone system over the phone network using serial protocols (SMDI, MCI, or MD-110).

The phone system sends call information and MWI requests through the data link, which is an RS-232 serial cable that connects the phone system and the master TIMG unit. Voice connections are sent through the T1 digital lines between the phone system and the TIMG units. The TIMG units communicate with the Cisco Unity Connection server through the LAN or WAN using Session Initialization Protocol (SIP). Figure 11-5 shows the connections for a serial integration using TIMG units.

Figure 11-5 Connections for a Serial Integration Using TIMG Units

TIMG In-Band Integration

The phone system sends call information, MWI requests, and voice connections through the T1 digital lines, which connect the phone system and the TIMG units. The TIMG units communicate with the Cisco Unity Connection server through the LAN or WAN using Session Initialization Protocol (SIP). Figure 11-6 shows the required connections for an in-band integration using TIMG units.

Figure 11-6 Connections for an In-Band Integration Using TIMG Units

PIMG/TIMG Integrations and Cisco Unified Communications Manager Through Cisco Unified SIP Proxy

The Cisco Unified SIP Proxy allows the PIMG/TIMG integrations and Cisco Unified Communications Manager to share the same voice messaging ports on Cisco Unity Connection by acting as a SIP proxy. The Cisco Unified SIP Proxy uses a SIP trunk integration with Unity Connection. Figure 11-7 shows the connections. For more information, see the application notes for Cisco Unified SIP Proxy at http://www.cisco.com/en/US/solutions/ns340/ns414/ns728/interOp_sipProxy.html.

Figure 11-7 Connections for PIMG/TIMG and Cisco Unified Communications Manager Through Cisco Unified SIP Proxy

Settings in the Phone System in Unity Connection

For an integration to be successful, Unity Connection and the phone system must know the connections to use (for example, IP addresses and channels) and the expected method of communication (for example, IP packets, serial packets, and DTMF tones). Certain integrations require specific codes or extensions for turning MWIs on and off.

There are required settings for Unity Connection, and programming for the phone system, that must be made in order to enable the integration. For information on these settings, see the applicable Cisco Unity Connection integration guide at http://www.cisco.com/en/US/products/ps6509/products_installation_and_configuration_guides_list.html.

Call Information Exchanged by the Phone System and Unity Connection

The phone system and Unity Connection exchange call information to manage calls and to make the integration features possible. With each call, the following call information is typically passed between the phone system and Unity Connection:

• 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 phone system supports caller ID).
• The reason for the forward (the extension is busy, does not answer, or is set to forward all calls). There is also a reason code for Direct Calls.

Cisco Unified Communications Manager SCCP and SIP trunk integrations can also provide the following call information:

• Called number
• First redirecting number
• Last redirecting number

Note Unity Connection can use either the first redirecting number or last redirecting number, depending on the setting of the Use Last (Rather than First) Redirecting Number for Routing Incoming Call check box on the System Settings > Advanced > Conversations page in Cisco Unity Connection Administration.

If the phone system sends the necessary information and if Unity Connection is configured correctly, an integration can provide the following integration functionality:

• Call forward to personal greeting
• Call forward to busy greeting
• Caller ID
• Easy message access (a user can retrieve messages without entering an ID because Unity Connection identifies the user based on the extension from which the call originated; a password may be required)
• Identified user messaging (Unity Connection identifies the user who leaves a message during a forwarded internal call, based on the extension from which the call originated)

Call Control

The phone system uses a set of signals to set up, monitor, and release connections for a call. Cisco Unity Connection monitors call control signals to determine the state of the call, and uses these signals to respond appropriately to phone system actions and to communicate with the phone system. For example, a caller who is recording a message might hang up, so Unity Connection detects that the call has ended and stops recording.

Depending on the phone system, the following types of call control signals are used:

Note If Extension A calls Extension B and if the Display Name or ASCII Alerting Name of Extension B contains the word “Voicemail”, then the call arrives on Cisco Unity Connection as a Direct Call rather than as a forwarded Call.

.Sample Path for a Call from the Phone System to a User

The following steps give an overview of a sample path that an external call can take when traveling from the phone system to a user.

1. For Cisco Unified Communications Manager, when an external call arrives, the gateway sends the call over the LAN or WAN to Cisco Unified CM. Cisco Unified CM routes the call to the Cisco Unity Connection voice mail pilot number.

For circuit-switched phone systems, when an external call arrives via the PSTN, TI/PRI, DID or LS/GS analog trunks, the phone system routes the call to the Cisco Unity Connection voice mail pilot number.

2. The phone system routes the call to an available Cisco Unity Connection voice messaging port.

3. Unity Connection answers the call and plays the opening greeting.

4. During the opening greeting, the caller enters an extension. For example, the caller enters 1234 to reach a person at that extension.

5. Unity Connection notifies the phone system that there is a call for extension 1234.

6. Depending on whether Unity Connection is set up to perform a release transfer or a supervised transfer, the following occurs:

Cisco Unified Communications Manager Authentication and Encryption for Cisco Unity Connection Voice Messaging Ports

A potential point of vulnerability for a Cisco Unity Connection system is the connection between Unity Connection and Cisco Unified Communications Manager. Possible threats include:

• Man-in-the-middle attacks, in which an attacker intercepts and changes the data flowing between Cisco Unified CM and Unity Connection voice messaging ports.
• Network traffic sniffing, in which an attacker captures phone conversations and signaling information that flow between Cisco Unified CM, the Unity Connection voice messaging ports, and IP phones that are managed by Cisco Unified CM.
• Changing the call signaling between the Unity Connection voice messaging ports and Cisco Unified CM.
• Changing the media stream between Unity Connection voice messaging ports and endpoints, for example, phones or gateways.
• Identity theft of the Unity Connection voice messaging port, in which a non-Unity Connection device presents itself to Cisco Unified CM as a Unity Connection voice messaging port.
• Identity theft of the Cisco Unified CM server, in which a non-Cisco Unified CM server presents itself to Unity Connection voice messaging ports as a Cisco Unified CM server.

See the following sections for additional details:

• Cisco Unified Communications Manager Security Features
• When Data Is Encrypted
• Cisco Unified Communications Manager Cluster Security Mode Settings in Cisco Unity Connection
• Disabling and Reenabling Security
• Multiple Clusters Can Have Different Security Mode Settings
• Settings for Individual Voice Messaging Ports
• Packetization

Cisco Unified Communications Manager Security Features

Cisco Unified Communications Manager Release 4.1(3) or later for SCCP integrations or Cisco Unified Communications Manager Release 5.x or later for SIP trunk integrations can secure the connection with Cisco Unity Connection against security threats. The Cisco Unified CM security features that Unity Connection can take advantage of are described in Table 11-2 .

Note that Cisco Unified CM authentication and encryption protects only calls to Unity Connection. Messages that are recorded on Unity Connection are not protected by Cisco Unified CM authentication and encryption but can be protected by the Unity Connection secure messaging feature.

For more information on secure messaging, see the “Securing User Messages in Cisco Unity Connection 10.x” chapter of the Security Guide for Cisco Unity Connection Release 10.x, at http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/connection/10x/security/guide/10xcucsecx/10xcucsec070.html.

The security features (authentication and encryption) between Unity Connection and Cisco Unified CM require the following for SCCP integrations:

• A Cisco Unified CM CTL file that lists all Cisco Unified CM servers that are entered in Cisco Unity Connection Administration for secure clusters.
• A Unity Connection server root certificate for each Unity Connection server that uses authentication and/or encryption. A root certificate is valid for 7 years from the time it was created.
• Unity Connection voice messaging port or port group device certificates that are rooted in the Unity Connection server root certificate, and voice messaging ports or port groups that are present when registering with the Cisco Unified CM server.

The process of authentication and encryption of Unity Connection voice messaging SCCP ports occurs as follows:

1. Each Unity Connection voice messaging port connects to the TFTP server, via TFTP port 69, downloads the CTL file, and extracts the certificates for all Cisco Unified CM servers.

2. Each Unity Connection voice messaging port establishes a network connection to the Cisco Unified CM TLS port. By default, the TLS port is 2443, though the port number is configurable.

3. Each Unity Connection voice messaging port establishes a TLS connection to the Cisco Unified CM server, at which time the device certificate is verified and the voice messaging port is authenticated.

4. Each Unity Connection voice messaging port registers with the Cisco Unified CM server, specifying whether the voice messaging port will also use media encryption.

The process of authentication and encryption of Unity Connection voice messaging SIP port groups occurs as follows:

1. Each Unity Connection voice messaging port group connects to the TFTP server, via TFTP port 69, downloads the CTL file, and extracts the certificates for all Cisco Unified CM servers.

2. Each Unity Connection voice messaging port group establishes a network connection to the Cisco Unified CM TLS port. By default, the TLS port is 2443, though the port number is configurable.

3. Each Unity Connection voice messaging port group establishes a TLS connection to the Cisco Unified CM server, at which time the device certificate is verified and the voice messaging port group is authenticated.

4. Each Unity Connection voice messaging port group registers with the Cisco Unified CM server, specifying whether the voice messaging port group will also use media encryption.

When Data Is Encrypted

When a call is made between Cisco Unity Connection and Cisco Unified CM, the call-signaling messages and the media stream are handled in the following manner:

• If both endpoints are set for encrypted mode, the call-signaling messages and the media stream are encrypted.
• If one endpoint is set for authenticated mode and the other endpoint is set for encrypted mode, the call-signaling messages are authenticated. But neither the call-signaling messages nor the media stream are encrypted.
• If one endpoint is set for non-secure mode and the other endpoint is set for encrypted mode, neither the call-signaling messages nor the media stream are encrypted.

Cisco Unified Communications Manager Cluster Security Mode Settings in Cisco Unity Connection

The Security Mode settings in Cisco Unity Connection Administration determine how the ports handle call-signaling messages and whether encryption of the media stream is possible. Table 11-3 describes the effect of the Security Mode settings on the Telephony Integrations > Port > Port Basics page for each port in an SCCP integration.

Table 11-3 Security Mode Settings for Voice Messaging Ports in an SCCP Integration

Setting	Effect
Non-secure	The integrity and privacy of call-signaling messages will not be ensured because call-signaling messages are sent as clear (unencrypted) text and are connected to Cisco Unified CM through a non-authenticated port rather than an authenticated TLS port. In addition, the media stream cannot be encrypted.
Authenticated	The integrity of call-signaling messages is ensured because they are connected to Cisco Unified CM through an authenticated TLS port. However, the privacy of call-signaling messages is not ensured because they are sent as clear (unencrypted) text. In addition, the media stream is not encrypted. Note You can ensure the integrity of call-signaling messages for the audio a calls using the authenticated TLS port.
Encrypted	The integrity and privacy of call-signaling messages is ensured because they are connected to Cisco Unified CM through an authenticated TLS port, and the call-signaling messages are encrypted. In addition, the media stream can be encrypted. Caution Both endpoints must be registered in encrypted mode for the media stream to be encrypted. However, when one endpoint is set for non-secure or authenticated mode and the other endpoint is set for encrypted mode, the media stream is not encrypted. Also, if an intervening device (such as a transcoder or gateway) is not enabled for encryption, the media stream is not encrypted.

Disabling and Reenabling Security

The authentication and encryption features between Cisco Unity Connection and Cisco Unified CM can be enabled and disabled by changing the Security Mode for all Cisco Unified CM clusters to Non-Secure, and by changing the applicable settings in the Cisco Unified Communications Manager Administration.

Authentication and encryption can be reenabled by changing the Security Mode to Authenticated or Encrypted.

Note After disabling or re-enabling authentication and encryption, it is not necessary to export the Unity Connection server root certificate and copy it to all Cisco Unified CM servers.

Multiple Clusters Can Have Different Security Mode Settings

When Cisco Unity Connection has multiple Cisco Unified CM phone system integrations, each Cisco Unified CM phone system integration can have different Security Mode settings. For example, one Cisco Unified CM phone system integration can be set to Encrypted, and a second Cisco Unified CM phone system integration can be set to Non-Secure.

Settings for Individual Voice Messaging Ports

For troubleshooting purposes, authentication and encryption for Cisco Unity Connection voice messaging ports can be individually enabled and disabled. At all other times, the Security Mode setting for all individual voice messaging ports in a Cisco Unified CM port group should be the same.

Packetization

The Real-Time Transport Protocol (RTP) is used to send and receive audio and video packets over the IP network. Each discrete packet has a fixed-size header, but the packets themselves can vary in size, depending on the size of the audio stream to be transported (which varies by codec) and the packetization setting. This variable size function helps utilize network bandwidth more efficiently. Reducing the number of packets that are created per call sends fewer total bytes over the network.

Packetization is set in the Cisco Unified CM Service Parameters, in the Preferred G711 Millisecond PacketSize and Preferred G729 Millisecond PacketSize parameters. Cisco Unity Connection supports any packet size up to 30ms for G.711 audio, and any packet size up to 60 ms for G.729a audio. The default setting is 20ms for both; there may be latency issues with lower settings.

DSCP is a priority setting on each packet. DSCP helps intermediary routers manage network congestion and lets them know which packets to prioritize ahead of others. Following Cisco AVVID standards, Unity Connection marks the SCCP and SIP packets (call control) with a default DSCP value of 24 (the TOS octet is 0x60), and the RTP packets (audio and video traffic) with a default DSCP value of 46 (the TOS octet is 0xB8). Thus, the RTP audio and video packets can be assigned priority over other packets using the router settings. Note that even though Cisco Unified CM allows you set different DSCP values, when integrated with Unity Connection, the DSCP values set by Unity Connection always take precedence. The marking of both SCCP and SIP packets is configurable in Unity Connection on the System Settings > Advanced > Telephony Configuration page in Cisco Unity Connection Administration.

With each new audio stream (once per call), Cisco Unified CM tells Unity Connection which packet size to use, and Unity Connection sets the DSCP priority for the stream. The entire stream (call) stays at the specified packet size and priority. For example, an audio stream could be broken up into packets of 30ms each. A 30ms G.729a audio stream would be 30 bytes plus the header per packet, and a 30ms G.711 stream would be 240 bytes plus the header per packet. For information on setting Cisco Unified CM Service Parameters, see the Cisco Unified CM documentation at http://www.cisco.com/en/US/products/sw/voicesw/ps556/tsd_products_support_series_home.html.

Note You can change the codecs that Unity Connection advertises on the Telephony Integrations > Port Group > Edit Codec Advertising configuration page in Cisco Unity Connection Administration.

For a discussion of supported advertised or “on the line” audio codecs and system-level recording audio codecs, see the “Audio Codecs” section.

Port Group Configuration for Cisco Unified Communications Manager Cluster Failover

For Cisco Unified Communications Manager SCCP integrations, when a Cisco Unified CM cluster is configured and Cisco Unified CM failover occurs as calls are in progress, the voice messaging ports may experience a delay registering with the secondary Cisco Unified CM server.

Unity Connection ports can register more quickly after Cisco Unified CM failover occurs if the port groups are configured as follows:

• You create two port groups for the SCCP integration:

– The first port group contains half the voice messaging ports for the Cisco Unified CM integration (including answering and dialout ports) configured as described in the applicable chapter of the Cisco Unified Communications Manager SCCP Integration Guide for Cisco Unity Connection Release 10.x.

– The second port group contains the remaining half of the ports for the Cisco Unified CM integration (including answering and dialout ports) as described in the applicable chapter of the same guide.

Note The Cisco Unified Communications Manager SCCP Integration Guide for Cisco Unity Connection Release 10.x. is available at http://www.cisco.com/en/US/docs/voice_ip_comm/connection/10x/integration/guide/cucm_sccp/cucintcucmskinny.html.

• On the Telephony Integrations > Port Group > Port Group Basics > Edit Servers page, you list the Cisco Unified CM servers in different orders:

– For the first port group, the Cisco Unified CM servers are listed in the order specified in the applicable chapter of the Cisco Unified Communications Manager SCCP Integration Guide for Cisco Unity Connection Release 10.x.

– For the second port group, the Cisco Unified CM servers are listed in the reverse order.

Internet Protocol Version 6 (IPv6) Support with Cisco Unified Communications Manager Integrations

Cisco Unity Connection supports IPv4, IPv6, or dual-stack (IPv4 and IPv6) addressing with Cisco Unified Communications Manager phone system integrations via SCCP or SIP. When IPv6 is enabled, Connection can obtain an IPv6 address either through router advertisement, through DHCP, or by manually configuring an address either in Cisco Unified Operating System Administration or using the command-line interface.

For SCCP integrations with Cisco Unified CM, if Unity Connection is configured to listen for incoming IPv4 and IPv6 traffic, you can configure the addressing mode that Unity Connection uses for call control signaling for each port group to use either IPv4 or IPv6. (This mode is also used when connecting to a TFTP server.)

For SIP integrations with Cisco Unified CM, if Unity Connection is configured to listen for incoming IPv4 and IPv6 traffic, you can configure the addressing mode that Unity Connection uses for call control signaling for each port group to use either IPv4 or IPv6. (This mode is also used when connecting to a TFTP server.) In addition, you can configure the addressing mode that Unity Connection uses for media for each port group to use either IPv4 or IPv6.

IPv6 support is disabled by default. You can enable IPv6 and configure IPv6 address settings either in Cisco Unified Operating System Administration or in the CLI. For information on enabling and configuring IPv6 when setting up a new Cisco Unified CM integration, see the applicable Cisco Unity Connection integration guide at http://www.cisco.com/en/US/products/ps6509/products_installation_and_configuration_guides_list.html.

Note the following considerations when deploying IPv6 for Cisco Unified CM integrations:

• The CTL file required for security features (authentication and encryption) between Unity Connection and Cisco Unified CM for SCCP integrations uses IPv4 addressing. Therefore, in order to use authentication and/or encryption with SCCP, you must use either IPv4 or dual-stack addressing.
• Some versions of Cisco Adaptive Security Appliance (ASA) do not support application inspection for IPv6 traffic for Unified Communications application servers and endpoints. You should not be using IPv6 for Unified Communications if you are using a Cisco ASA version that does not provide this support. See the documentation for your version of Cisco ASA to determine whether application inspection is supported in your deployment.

Multiple Cisco Unified Communications Manager Express Version Support

A single Cisco Unity Connection server can support multiple versions of Cisco Unified CM Express. The version of Unity Connection being used must support all versions of Cisco Unified CM Express. See the following documents:

• SCCP Compatibility Matrix: Cisco Unity Connection, Cisco Unified Communications Manager, and Cisco Unified Communications Manager Express at http://www.cisco.com/en/US/docs/voice_ip_comm/connection/compatibility/matrix/cucsccpmtx.html.
• SIP Trunk Compatibility Matrix: Cisco Unity Connection, Cisco Unified Communications Manager, and Cisco Unified Communications Manager Express at http://www.cisco.com/en/US/docs/voice_ip_comm/connection/compatibility/matrix/cucsiptrunkmtx.html.

Multiple Cisco Unified Communications Manager Express Routers Integrating with a Single Cisco Unity Connection Server

A single, centralized Cisco Unity Connection server can be used by multiple Cisco Unified CM Express routers. This configuration requires that one Cisco Unified CM Express router be on the same LAN as the Unity Connection server, and that this Cisco Unified CM Express router register all Unity Connection voice messaging ports. This Cisco Unified CM Express router (the SIP MWI server) is a proxy server that relays SIP MWI messages between the Unity Connection server and all other Cisco Unified CM Express routers (the SIP MWI clients). Note that Unity Connection voice messaging ports register only with the SIP MWI server (the Cisco Unified CM Express router that is on the same LAN as the Unity Connection server), not with the SIP MWI clients. See Figure 11-9.

Figure 11-9 Connections between Multiple Cisco Unified CM Express Routers and a Single Cisco Unity Connection Server

For information on configuring Unity Connection to support multiple Cisco Unified CM Express routers, see the applicable Cisco Unity Connection integration guide at http://www.cisco.com/en/US/products/ps6509/products_installation_and_configuration_guides_list.html.

Impact of Non-Delivery of RDNIS on Voice Mail Calls Routed Using AAR

RDNIS must be supported when using Automated Alternate Routing (AAR).

AAR can route calls over the PSTN when the WAN is oversubscribed. However, when calls are rerouted over the PSTN, RDNIS can be affected. Incorrect RDNIS information can affect voice mail calls that are rerouted over the PSTN by AAR when Cisco Unity Connection is remote from its messaging clients. If the RDNIS information is not correct, the caller does not reach the mailbox of the dialed user but instead hears the automated attendant prompt, and might be asked to reenter the extension number of the party the caller wants to reach. This behavior is primarily an issue when the phone carrier is unable to ensure RDNIS across the network. There are numerous reasons why the carrier might not be able to ensure that RDNIS is properly sent. Check with your carrier to determine whether it provides guaranteed RDNIS delivery end-to-end for your circuits. The alternative to using AAR for oversubscribed WANs is simply to let callers hear reorder tone in an oversubscribed condition.

Integrating Cisco Unity Connection with Cisco Unified Communications Manager Express in SRST Mode

Cisco Unity Connection supports a topology with centralized call processing and distributed messaging, in which your Unity Connection server is located at a remote site or branch office and registered with Cisco Unified CM at a central site.

When the WAN link fails, the phones fall back to the Cisco Unified CM Express-as-SRST device. Unity Connection can also fall back to the Cisco Unified CM Express-as-SRST device, which lets users at the remote site access their voice messages and see message waiting indicators (MWIs) during a WAN outage. Note that MWIs must be resynchronized from the Unity Connection server whenever a failover happens from Cisco Unified CM to Cisco Unified CM Express-as-SRST or vice versa.

For information on setting up this configuration, see the Integrating Cisco Unity Connection with Cisco Unified CME-as-SRST configuration guide at http://www.cisco.com/en/US/products/sw/voicesw/ps4625/products_installation_and_configuration_guides_list.html.

Supported SIP Integrations

Cisco Unity Connection supports the following SIP integrations:

• SIP trunks to supported versions of Cisco Unified Communications Manager and Cisco Unified Communications Manager Express. For a list of Cisco Unified CM and Cisco Unified CM Express versions supported as SIP trunks, see SIP Trunk Compatibility Matrix: Cisco Unity Connection, Cisco Unified Communications Manager, and Cisco Unified Communications Manager Express at http://www.cisco.com/en/US/docs/voice_ip_comm/connection/compatibility/matrix/cucsiptrunkmtx.html.
• Cisco SIP Proxy Server (CSPS).
• Cisco ISR voice gateways for integrating Unity Connection to a QSIG-enabled phone system (see the “Integrating Unity Connection with a QSIG-Enabled Phone System Using Cisco ISR Voice Gateways” section).

Third-party SIP trunks are currently not supported.

For more information on configuring SIP trunks between Unity Connection and Cisco Unified CM or Cisco Unified CM Express, see the applicable SIP trunk integration guide at http://www.cisco.com/en/US/products/ps6509/products_installation_and_configuration_guides_list.html.

Note Cisco Unity Connection extracts Caller Id from Remote Party Id field and FROM field in SIP Invite. In addition, when the Remote Party Id option is unchecked on CUCM SIP trunk and the FROM field is set to Anonymous in a SIP header, Connection treats the caller as unknown.

Description of PIMG Integrations

The PIMG integration uses one or more PIMG units between the circuit-switched phone systems and IP network. On the circuit-switched phone system side, there are both digital (feature-set) and analog interfaces; the interface used depends on the phone system to which Cisco Unity Connection is connected. On the IP side, there is a SIP interface, which is how Unity Connection communicates with the PIMG units. To Unity Connection, the integration is essentially a SIP integration. Unity Connection communicates with the PIMG units over the IP network using SIP and RTP protocols. The PIMG units communicate with the circuit-switched phone system over the phone network using phone system-specific protocols (digital, analog, or serial).

For high-level descriptions of each PIMG integration type, and illustrations showing the network connections, see the “How a Phone System Integration Works” section.

Setup and Configuration

For PIMG/TIMG setup and configuration, the installer does the following steps as documented in the applicable integration guide:

1. Configure the phone system.

2. Configure the PIMG/TIMG units. PIMG/TIMG settings are somewhat phone system-specific, but less so than phone system configuration.

3. Configure Cisco Unity Connection for the integration.

For information on configuring the phone system, PIMG/TIMG units, and Unity Connection, see the applicable Cisco Unity Connection integration guide at http://www.cisco.com/en/US/products/ps6509/products_installation_and_configuration_guides_list.html.

Firmware Updates

Note that when receiving shipment of PIMG or TIMG units, it may be necessary to update the firmware on the units. The PIMG/TIMG Administration interface provides a simple method to update the firmware files. Firmware updates are available at http://tools.cisco.com/support/downloads/go/Redirect.x?mdfid=278875240 (note that you must sign in to www.cisco.com to access the URL). For details, see the applicable integration guide.

Serial Integrations

Cisco Unity Connection supports the following serial protocols:

• SMDI
• MCI
• MD-110

The serial port on PIMG/TIMG units was originally designed as a management port rather than as a standard RS-232 serial port. Consequently, a custom serial cable (which is available from Cisco) is necessary for the data link between the phone system and the master PIMG/TIMG unit.

Increasing Port Capacity

PIMG units have eight ports. To increase system port capacity, multiple PIMG units can be stacked. For example, if 32 ports are needed, four PIMG units can be stacked.

TIMG units, which integrate with circuit-switched phone systems that support T1-CAS, have 24 T1 ports per span in a single rack-optimized unit. Single-span, dual-span, and quad-span TIMG units are available.

Unity Connection Clusters

PIMG/TIMG integrations support Unity Connection clusters (active/active high availability). Configuration changes are required both for the PIMG/TIMG units and for the Unity Connection servers, as described in the applicable Cisco Unity Connection integration guide at http://www.cisco.com/en/US/products/ps6509/products_installation_and_configuration_guides_list.html.

Multiple Integration Support/Branch Office Consolidation

PIMG/TIMG units can be separated by a WAN to support circuit-switched phone systems at remote branch office sites. For example, Cisco Unity Connection could be placed at a centralized headquarters and support circuit-switched phone systems both at the headquarters and at the branch office sites.

As an example, assuming there are four phone systems from four different manufacturers (for example, Nortel, Avaya, NEC, and Siemens), four different phone system integrations could be created on the Unity Connection server to support the four phone systems. A standalone Unity Connection server supports up to 144 ports that will connect to the four phone systems. For example:

• At the Seattle site, 15 PIMG units can be stacked to support 120 ports.
• At the New York site, two PIMG units can be stacked to support 16 ports.
• At the Tokyo site, one PIMG unit can be used to support four ports.
• At the Dallas site, one PIMG unit can be used to support two ports.

Note that even though the PIMG units come with eight ports, fewer than eight ports can be used on each unit.

If PIMG units will be separated by a WAN to support remote phone systems, correct audio codec selection, bandwidth capacity planning, and QOS planning are required. Both the G.729a and G.711 audio codecs are supported by PIMG units and by Unity Connection. Because PIMG units are Dialogic devices rather than Cisco devices, the use of location-based CAC is not applicable. The following network and bandwidth requirements are required when placing the PIMG across a WAN:

• For the G.729a audio codec, a minimum of 32.76 Kbps (assumes Ethernet, payload of 20 bytes, 5 percent overhead) guaranteed bandwidth for each voice messaging port.
• For the G.711 audio codec, a minimum of 91.56 Kbps (assumes Ethernet, payload of 160 bytes, 5 percent overhead) guaranteed bandwidth for each voice messaging port.
• No network devices that implement network address translation (NAT).

When PIMG units are separated by a WAN, prioritize your call control and media traffic through proper QOS traffic, marking for voice traffic originating on the PIMG units. Set the Call Control QOS Byte and RTP QOS Byte on PIMG units to the following values:

• In the Call Control QOS Byte field, enter 104.
• In the RTP QOS Byte field, enter 184.

Note that the Call Control QOS Byte and RTP QOS Byte fields on PIMG units define a decimal value that represents QOS bit flags. These values can be interpreted as either IPv4 TOS or Differentiated Services Codepoint (DSCP). For more details, see the Dialogic 1000 and 2000 Media Gateway Series User’s Guide, provided by Dialogic.

Requirements for Integrations with Multiple Phone Systems

Cisco Unity Connection has the following requirements for multiple phone system integrations:

• All phone system and Unity Connection server requirements have been met. See the applicable Cisco Unity Connection integration guide at http://www.cisco.com/en/US/products/ps6509/products_installation_and_configuration_guides_list.html.
• There must be an adequate number of voice messaging ports on the Unity Connection server to connect to the phone systems.

Optional Integration Features

See the following sections:

• Alternate Extensions
• Alternate MWIs

Alternate Extensions

Revised April, 2014

In addition to the primary extension for each user, you can set up alternate extensions. Alternate extensions can be used for various reasons, such as handling multiple line appearances on user phones. Alternate extensions can also make calling Cisco Unity Connection from an alternate device—such as a mobile phone, a home phone, or a phone at another work site—more convenient.

When you specify the phone number for an alternative extension, Unity Connection handles all calls from that number in the same way that it handles calls from a primary extension (assuming that ANI or caller ID is passed along to Unity Connection from the phone system). This means that Unity Connection associates the alternate phone number with the user account, and when a call comes from that number, Unity Connection prompts the user to enter a password and sign in.

See the following sections:

• URI Dialing for Alternate Extensions
• Directory URI Format

URI Dialing for Alternate Extensions

Added April 11, 2014

Unity Connection supports dialing using URIs for alternate extensions. URIs look like email addresses and follow the username@host format where the host portion is an IPv4 address or a fully qualified domain name. A URI is a uniform resource identifier, a string of characters that can be used to identify a directory number. If that directory number is assigned to a phone then Cisco Unity Connection can route calls to that phone using the URI. URI dialing is available for both SIP endpoints that support URIs.

The administrator can import the end users directory URI into Unity Connection from the LDAP directory or Cisco Unified Communications Manager.

Note In HTTPS, CCI, and Diginet networking, URI for alternate extensions is replicated only on the nodes that support directory URI.

Directory URI Format

URIs are alphanumeric strings consisting of a user and a host address separated by the @ symbol. The URI field has a maximum length of 40 characters.

Unity Connection supports the following formats for URIs:

• user@domain (for example, joe@cisco.com)
• user@ip_address (for example, joe@10.10.10.1)

Unity Connection supports the following formats in the user portion of a URI (the portion before the @ symbol):

• Accepted characters are a-z, A-Z, 0-9, !, $, %, &, *, _, +, ~, -, =, \, ?, \, ',,,., /, "", {}, []. <>.
• The user portion is case sensitive.

Unity Connection supports the following formats in the host portion of a URI (the portion after the @ symbol):

• Supports IPv4 addresses or fully qualified domain names.
• Accepted characters are a-z, A-Z,0-9, hyphens, and dots.
• The host portion cannot start or end with a hyphen.
• The host portion cannot have two dots in a row.
• Minimum of one character.
• The host portion is case sensitive.

Note Use lower case for URIs.

Alternate MWIs

You can set up Cisco Unity Connection to activate alternate MWIs when you want a new message for a user to activate the MWIs at up to 10 extensions. For example, a message left at extension 1001 can activate the MWIs on extensions 1001 and 1002.

Unity Connection uses MWIs to alert the user to new voice messages. MWIs are not used to indicate new email, fax, or return receipt messages.

Centralized Voice Messaging

Cisco Unity Connection supports centralized voice messaging through the phone system, which supports various inter-phone system networking protocols including proprietary protocols such as Avaya DCS, Nortel MCDN, or Siemens CorNet, and standards-based protocols such as QSIG or DPNSS. Note that centralized voice messaging is a function of the phone system and its inter-phone system networking, not voice mail. Unity Connection will support centralized voice messaging as long as the phone system and its inter-phone system networking are properly configured.

When discussing phone systems involved in centralized voice messaging, there are essentially two types:

• Message Center PINX —The phone system hosts the voice messaging system (the phone system is directly connected to the voice messaging system).
• User PINX —The phone system is remote from the voice messaging system (the phone system is not directly connected to the voice messaging system).

Centralized voice messaging provides voice messaging services to all users in a networked phone system environment. Unity Connection can be hosted on a message center PINX and provide voice messaging services to all users in an enterprise assuming the message center PINX and all user PINX phone systems are properly networked.

For a centralized voice messaging configuration to exist, a suitable inter-phone system networking protocol must exist to deliver a minimum level of feature support, such as:

• Message waiting indication (MWI).
• Transfer, which ensures that the correct calling/called party ID is delivered to the voice messaging system.
• Divert, which ensures that the correct calling/called party ID is delivered to the voice messaging system.

Other features may be required depending on how the voice messaging system is to be used. For example, if it is also serving as an automated attendant, path-replacement is needed as this feature prevents calls from hair-pinning.

Not all phone systems can serve as a message center PINX. In this case, customers may wish to consider relocating Unity Connection to Cisco Unified Communications Manager and have Cisco Unified CM act as the message center PINX with the circuit-switched phone system now acting as the user PINX.

For information on configuring Unity Connection in a centralized voice messaging environment to be hosted on Cisco Unified CM serving as the message center PINX, see the following:

• The application note Cisco CallManager 4.1-Voicemail Interoperability: Cisco Unity 4.0(4) with Cisco CallManager 4.1(2) Configured as Message Center PINX Using Cisco Catalyst 6608 T1 Q.SIG with MGCP at http://www.cisco.com/en/US/docs/voice_ip_comm/cucme/pbx/interop/notes/414111.pdf.
• The applicable application note for configuring QSIG trunks between Cisco Unified Communications Manager and various circuit-switched phone systems on the Cisco Interoperability Portal at http://www.cisco.com/en/US/netsol/ns728/networking_solutions_products_generic_content0900aecd805b561d.html.

Note that if customers are deploying centralized voice messaging with Unity Connection and a circuit-switched phone system, it is up to the customer to determine whether the circuit-switched phone system can serve as a message center PINX on which Unity Connection can be hosted. If so, the customer should also confirm that there is support for the desired features, for example, MWIs, transfer, divert, and path-replacement.

Inter-cluster trunks between Cisco Unified CM clusters can be QSIG-enabled using the Annex M.1 feature, which allows Unity Connection to integrate with a single Cisco Unified CM cluster. Ports in the cluster with which Unity Connection is integrated can be dedicated to turning MWIs on and off for phones in other clusters.