7.7.1 Types of Carriers
Since individual carriers often provide specific connections and conditions at different tariffs (with
different signalling methods, when applicable), the least cost routing feature can be used for
automatically selecting the most economical connection or most economical carrier for each outgoing
phone call.
The following carrier types and networks are available for implementing least cost routing (LCR).
7.7.1.1 Cable & Wireless Communications PLC "single stage"
Definition
With this type of LCR, the relevant carrier is selected by means of a prefix, after which the extension
number is dialled.
Model-Specific Data
Subject OfficePro OfficeCom OfficePoint OfficeOne
Feature available in x x x x
HW requirements - - - -
SW requirements As of Rel. 1.0 As of Rel. 1.0 As of Rel. 1.0 As of Rel. 1.0
Dependencies/Limitations
Subject Dependency/Limitation
C&W single stage The number is dialled via the D channel (for ISDN) or as normal with loop start.
7.7.1.2 Cable & Wireless Communications PLC "two stage"
Definition
With this type of least cost routing, the system first selects the carrier by means of a configurable
access code as with "single stage". It then also waits for a "Connect" signal (synchronisation during
timeout).
After the "Connect" signal is received, an authorisation code and destination extension number are
transmitted as DTMF signals via the B channel.
Model-Specific Data
Subject OfficePro OfficeCom OfficePoint OfficeOne
Feature available in x x x x
HW requirements - - - -
SW requirements As of Rel. 1.0 As of Rel. 1.0 As of Rel. 1.0 As of Rel. 1.0
Dependencies/Limitations
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