Directory Number Mapping - AT&T MERLIN LEGEND Reference

Overview
Each BRI line, called a Digital Subscriber Line (DSL), coming into the MERLIN
LEGEND system contains two Directory Numbers (DNs), one for each B-
channel. Usually the Directory Number is the number that is dialed to reach the
destination.
The MERLIN LEGEND system maps the Directory Number (DN) to a line
number in the Dial Plan. For example, if the 800 CO-BRI module is the first
module in the system, DN1 is mapped to Line 801, the first line in the MERLIN
LEGEND system. DN2 is mapped to 802, and soon for each DN (see Figure 1-
4). A telephone with Line 801 rings any time a call arrives to DN1. Subsequent
calls to the same DN can be handled by the 5ESS Multi-Line Hunt Group
feature (if the user has subscribed to this feature).
Figure 1-4. Directory Number Mapping
Every BRI line physically plugged into a port on an 800 CO-BRI module equates
to two MERLIN LEGEND lines. This is similar to the way one physical PRI line
plugged into a 100D module becomes 23 lines on the MERLIN LEGEND
system.
System Overview
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