Snom ONE IP, Техническое руководство

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Deploying the snom ONE IP Telephone System
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Parts of a Dial Plan
Key Components
A dial plan consists of the following key components:
•
Preference: The preference number is used to establish the preference order
that will be used by the system when searching for a trunk on which to route
a call. The system processes the available trunks beginning with the lowest
preference value. (Identical preference values can be used for different trunks
within the same dial plan; however, the system will randomly choose a trunk
when more than one trunk meets the given criteria, so you should preference
them.)
•
Trunk: The trunk setting allows you to designate trunks that will be used by
the dial plan. Trunks that are available for the domain are listed in the drop-
down menu, and additional trunks can be added. Once trunks have been
designated for a particular dial plan, the trunk that meets the pattern and
replacement criteria for a particular call will be used to process the call.
•
C and P: The C and P checkboxes determine how a call is handled once the
user dials out onto the trunk. If the C checkbox is selected, the user will be
prompted to enter a CMC code, but will not be required to. If the
P
checkbox
is selected, the user will be required to enter a PIN number. This can be used
to prevent unauthorized callers from making international calls. The
C and P
setting works in tandem with the CMC authentication for outbound calls
domain setting (see page 97). The CMC code can also be set from the
domain address book or the personal address book.
•
Pattern:
The pattern field is used to interpret digit sequences that will be used
to decide on routing. In most cases, simplified expressions consisting of liter-
als, prefixes, and fixed patterns will suffice.
—
Literals: If you want to match a specific number, just enter the exact
number (e.g., 911 ). The literal will be the first match in the expression.
—
Prefixes: Prefixes allow you to route numbers that begin with identical
prefixes through the same trunk. For example, by specifying the com-
mon prefix 9011 in the pattern field, all international numbers will be