Routing elements
124
System functions and features as of R3.0
syd-0367/1.3 – R3.0 – 03.2013
5. 4
Direct Dialling Plan (DDI plan)
Fig. 49
Direct dialling plans in relation to the other routing elements
Direct dialling is used to reach internal users directly from the public network or
from another PINX. The incoming call is linked with a call distribution element on
the basis of the call number's direct dial portion.
Within a direct dialling plan, number ranges are created by agreement with the
public network operator; these numbers match up with the anticipated direct dial
portions of the call numbers. In a three-digit direct dialling plan, for example,
number ranges of 300…399 and 500…549 are created.
Depending on the country in which the PBX is operated, the ISDN public exchange
may send the complete call number or only a part of it. If the complete call number
is sent, the digits that do not form part of the direct dialling number can be trun-
cated starting from the left using the setting
Truncate DDI
in the trunk group con-
figuration.