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Networking Guide for Cisco Unity Release 5.x (With Microsoft Exchange)
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Chapter 2 Digital Networking
Digital Networking Concepts and Definitions
• A subscriber places a phone call to another subscriber, and then leaves a message
When the subscriber has logged on to Cisco Unity, Cisco Unity can identify the message as being from
the subscriber, regardless of which Cisco Unity server the message recipient is homed on. In this case,
the phone system is not involved and the recipient phone does not ring. Instead, the message is sent via
Digital Networking.
Addressing Search Scopes
In addition to the automated attendant and directory handler search scopes mentioned above, a dialing
domain provides a means to set the scope for searches that Cisco Unity performs in the following cases:
• When a subscriber addresses a message
• When members are being added to a public or private distribution list
By default, the addressing search scope used for the above searches is set to search only among
subscribers on the local Cisco Unity server. You must expand the addressing search scope on each
Cisco Unity server to either the dialing domain or the global directory to enable messaging between
subscribers on different Cisco Unity servers. See the “Setting the Addressing Search Scope” section on
page 2-6 for information on how to expand the Addressing search scope.
Addressing Options for Subscribers in a Dialing Domain
After expanding the addressing search scope to either the dialing domain or the global directory,
subscribers address messages to subscribers on other Cisco Unity servers the same way that they address
messages to subscribers on the same Cisco Unity server: either by extension or by spelling the name.
Dialing Domains Shield Against Overlapping Numbering Plans
The two requirements for grouping Cisco Unity servers into a dialing domain are that the servers access
the same global directory and are integrated with the same phone system. However, the minimum
requirement for the basic messaging functionality provided by Digital Networking is that all of the
Cisco Unity servers access the same global directory, as Figure 2-1 illustrates.
Figure 2-1 Multiple Phone Systems But One Global Directory
Dialing
domain A
Global directory
69418
Unity 1
Networked
phone system
M
Phone system
Unity 2
Unity 3