Understanding Bridge Networking 307
Figure 10-29 Adding a New AMIS Subscriber
Understanding Bridge Networking
Bridge networking with Cisco Unity allows messages to be transferred between Cisco Unity
and Octel voice-mail servers within an Octel analog environment.
If you plan to implement Cisco Unity in an environment with Octel voice-mail servers, you
need to understand Bridge networking concepts and how it is implemented. This section
provides the information that you need to effectively and efficiently provide customers with
Bridge networking.
Remote Mailbox
Number of
Subscriber on the
Remote Voice
Messaging System
Type = AMIS
Location of
Remote AMIS
308 Chapter 10: Unified Communications Networking
To benefit fully from this section, it is recommended that you have these prerequisite skills and
Knowledge of Cisco Unity messaging call flow (see Chapter 1)
Knowledge of how Cisco Unity handles calls (see Chapter 2)
Understanding of the concepts presented in the “Cisco Unity Networking Fundamentals”
section of this chapter
Defining Bridge Networking
Cisco Unity Bridge is a gateway that runs on a server that allows Cisco Unity to communicate
with Octel nodes within an Octel analog network. On the Octel network, the Bridge appears as
another node on the network. This is similar to how Cisco Unity appears as a node on an AMIS
network. The Cisco Unity Bridge’s main function is to translate messages between two different
protocols. When the Bridge communicates with an Octel node, it actually places a call to the
Octel system, and then it uses the Octel analog protocol. When it communicates with the Cisco
Unity system Octel uses VPIM with proprietary extensions for added functionality. Because
VPIM uses TCP/IP to communicate, messaging between Cisco Unity and the Bridge can be
done over the Internet or a TCP/IP network using SMTP.
Bridge networking is a licensed feature of Cisco Unity and requires a separate Bridge server. If
you have multiple Cisco Unity servers in your organization, only one server needs to be
licensed for and designated as the Bridge server. For purposes of load balancing, you can add
more bridge servers. Bridge servers exist in a one-to-one relationship with Cisco Unity servers,
which means that if there are two Bridge servers, two Cisco Unity servers are required to be
configured for Bridge networking.
TIP To check whether your Cisco Unity server contains a license for Bridge networking, open the
license Manager by going to Start > Run > Programs > Unity > Licensing.
There, you will see all the features that are licensed, including the Bridge sessions. If the value
of Bridge sessions is greater than 1, then you are licensed for at least one session on the Cisco
Unity server.
You can find a list of supported Octel systems in the Cisco Unity Pre-Installation Guide found
at Cisco.com.
Understanding Bridge Networking 309
Figures 10-30 and 10-31 illustrate how the Cisco Unity Bridge can be implemented in an
enterprise’s messaging infrastructure.
Figure 10-30 illustrates using Cisco Unity Bridge with dual integration.
Figure 10-30 Cisco Unity with Dual Integration
When Cisco Unity is combined with Cisco Unity Bridge, it is a solution that is capable of
helping an organization manage the transition from legacy telephone equipment to a converged
IP network. In the diagram, Cisco Unity is integrated with two switches: a circuit-switched
(legacy) PBX and a Cisco CallManager. It can manage voice-mail accounts for subscribers with
either IP telephones or standard single-line extensions attached to a circuit-switched PBX. In
addition, Cisco Unity Bridge can send and receive voice-mail messages using Octel’s analog
messaging protocol through the analog lines that connect the legacy PBX and voice-mail
system. In this manner, an enterprise may maximize its return on investment on older telephone
equipment, while transitioning subscribers to an IP telephone network at a planned pace.
Figure 10-31 illustrates using Cisco Unity Bridge with Cisco CallManager.
IP Phones
Cisco Unity
Cisco Unity
Legacy Phone
with Microsoft Outlook
T-1 Line
Analog Lines
Message Store
Legacy PBX
Octel Voice Mail System

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