Lucent Technologies MERLIN LEGEND Release 6.1 System Manager's Manual page 433

MERLIN LEGEND Communications System Release 6.1
System Manager's Guide 555-661-118
Glossary
CCS
centralized
telephone
programming
Centralized Voice
Messaging
central office
Centrex
channel
channel service
unit
checksum
circuit-switched
data call
class of restriction
clear data channel
clock
synchronization
(common-channel signaling) Signaling in which one
channel of a group of channels carries signaling
information for each of the remaining channels, permitting
each of the remaining channels to be used to nearly full
capacity. In the system's 100D module, channel 24 can be
designated as the signaling channel for channels 1–23.
Programming of features on individual telephones;
performed at a central location by the system manager.
See also system programming and extension
programming.
The sharing of a voice messaging system by two or more
directly connected MERLIN LEGEND systems in a private
network. Available beginning in Release 6.1.
See CO .
Set of system features to which a user can subscribe on
telephone trunks from the local telephone company.
Telecommunications transmission path for voice and/or
data.
See CSU .
Sum of ones in a sequence of ones and zeros used to
detect or correct errors in data transmission.
Data call made through an exclusively established and
maintained connection between data stations .
See COR .
Clear data channels (also called unrestricted data
channels) allow the transmission of occurrences of more
than seven contiguous zero bits. If a clear data channel is
requested and only restricted channels are available, the
call will be rejected. See also restricted data channel.
When digital signals are transmitted over a
communications link, the receiving end must be
synchronized with the transmitting end to receive the digital
signals without errors using clock synchronization. A
system synchronizes itself by extracting a timing signal
from an incoming digital stream. All the digital facilities in a
network operate from a single common clock, preferably a
port connected to a digital PSTN facility on a hub system or
a system that connects two network systems. In this case,
all digital facilities specify a loop clock source. One system
in a network may be specified as a local clock source when
no functioning digital facility in the network is connected to
the PSTN. All other digital facilities then use this clock and
specify their clock sources as loop. Primary, secondary,
and tertiary clock sources are specified to allow backup
synchronization in the event that the primary source is out
of service.
Issue 1
August 1998
Page GL-6