Lucent Technologies MERLIN LEGEND 6 - Manual (Page 61)

MERLIN LEGEND Communications System Release 6.0
System Manager’s Guide
555-660-118
Issue 1
February 1998
About the System
Page 2-9 System Overview
2
and the parties had hung up, the lamp associated with each connecting cord
would go out and the operator knew that the call was complete and the cord could
be removed.
The first automatic switch was invented in 1892 by Almon B. Strowger, an
undertaker who realized that his competitor was getting all the undertaking
business in the town, referred by the town telephone operator—who was also the
competing undertaker’s wife! The Strowger switch was an electromechanical
device controlled by the caller’s telephone (
station switching).
Strowger’s switch was adapted for use in the Bell System in 1919. It was noisy
and not very flexible at offering new services but, because it was more cost-
effective than human operators, it was directly responsible for making telephone
service affordable and universal.
In 1938, the Bell System developed and installed the next innovation in
electromechanical switching, and it is still in use in some areas today. It had fewer
switches, a sophisticated control mechanism, and lower maintenance. However,
like its predecessor, it was not flexible because it couldn’t be programmed.
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 Lucent Technologies 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 2
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.