MERLIN LEGEND Communications System Release 6.1
System Programming and Maintenance (SPM)
555-661-140
Issue 1
August 1998
About This Book
Page xvi
Terms and Conventions Used
Terms and Conventions Used
In this document, the terms in the following list are used in preference to other,
equally acceptable terms for describing communications systems.
Lines, Trunks and Facilities
Facility
is a general term that designates a communications path between a
telephone system and the telephone company central office. Technically a
trunk
connects a switch to a switch, for example the MERLIN LEGEND
Communications System to the central office. Technically, a
line
is a loop-start
facility or a communications path that does not connect two switches (for
example, an intercom line or a Centrex line). However, in actual usage, the
terms
line
and
trunk
are often applied interchangeably. In this book, we use
line/trunk
and
lines/trunks
to refer to facilities in general. Specifically, we refer to
digital facilities
. We also use terms such as personal line, ground-start trunk,
Direct Inward Dialing (DID) trunk, and so on. When you talk to your local
telephone company central office, ask them which terms they use for the
specific facilities they connect to your system.
Some older terms have been replaced with newer terms. The following list
shows the old term on the left and the new term on the right:
trunk module line/trunk module
trunk jack line/trunk jack
station extension
station jack extension jack
analog data station modem data station
digital data station terminal adapter
7500B data station terminal adapter
analog voice and analog data station analog voice and modem data
digital voice and analog data station MLX voice and modem data
analog data only station modem data only station
digital data only station terminal adapter only station
7500B data only station terminal adapter only station
digital voice and digital data station MLX voice and terminal
adapter station
MLX voice and 7500B data station MLX voice and terminal
adapter station