Specifications

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Cisco IP Telephony Network Design Guide
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Chapter 5 Dial Plan Architecture and Configuration
Cisco CallManager Dial Plan Architecture
Figure 5-1 Goal of a Well-Designed Dial Plan
The dial plan for internal calls to IP phones registered with a Cisco CallManager
cluster is fairly simple. On initial configuration, an IP phone is assigned a
directory number (DN), which it maintains wherever it resides. Whenever the IP
phone registers with the Cisco CallManager cluster, it effectively updates the
Cisco CallManager cluster dynamically with its new IP address while maintaining
its same directory number. The internal dial length (number of digits dialed) for
internal calls is configurable.
IP WAN
PSTN
Primary voice path
Secondary voice path
Headquarters
Site B
V
Gatekeeper(s)
IP
IP
IP
V
IP
IP
IP
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