System Overview - AT&T MERLIN LEGEND Release 3.1 System Manager's Manual

System Overview

It was, therefore, a natural progression that led to the idea of using a computer,
with its inherent programmable flexibility, to control the switching operation. This
new generation of switching technology was called an electronic switching
system (ESS). With ever-increasing innovations in technology (beginning with
the AT&T No.1 ESS first installed in 1965), the AT&T 5ESS digital switching
system handles 100,000 lines and 650,000 telephone calls per hour. The newer
digital switching systems also interface easily with high-speed digital trunks.
As mentioned earlier, the MERLIN LEGEND Communications System is a switch
located on a company's premises, providing access to powerful features and
advanced telephone network applications and services.
System Overview
The MERLIN LEGEND Communications System can handle voice and data
simultaneously over the same lines, and voice features can enhance the use of
data communications. The system accommodates businesses with needs
ranging from a few telephones to over 100 telephones. Its modular design
allows easy expansion.
Many of the terms and concepts introduced in the beginning of this chapter are
used in the system. As illustrated in Figure 2–5, the system allows the
connection of incoming trunks from the telephone company's central office
(CO), connected through the system's control unit to telephones and other
system equipment, for example, a PC or fax machine.
There are various types of trunks that provide different functionality. Likewise, a
variety of telephones and other equipment can be connected to the system.
Depending on the trunks and the telephones and other equipment selected, a
wide array of features and add-on products ( applications ) can function
according to the needs of your company.
The rest of this chapter provides an overview of each primary system aspect:
Incoming trunks
Modes of operation
System components
Line/trunk and extension modules
Features
Applications
Programming the system
System capacities
Auxiliary components
Data communications capabilities
2–10
About the System