Paradyne comsphere 3615 User Manual

Page of 135
COMSPHERE DualFlow Data Service Units
Glossary-2
December 1996
3615-A2-GB20-20
CTS
The state of the Clear-to-Send lead (V.24 circuit 106).
Data Service Unit
(DSU)
A DCE device that interprets, interfaces, and provides timing and signal control
between a DTE device and a digital network.
Data Terminal Equipment
(DTE)
A computer or peripheral device, such as a terminal or printer; a data source or sink.
DBM
The dial backup module for the DualFlow DSU. This module provides an alternate
data path for carrying router data. Three types of DBMs are available: V.32 DBMs
(14.4 kbps) for backup through the PSTN (dial network), 4-wire Switched 56
DBMs for backup through the 4-wire Switched 56 kbps digital service, and 2-wire
Switched 56 DBMs for backup through the 2-wire Switched 56 kbps digital service.
(The 4-wire Switched 56 DBMs are only available in the U.S.)
DDS
Digital Data Service, such as ACCUNET Spectrum of Digital Services, that
provides digital (not dial) communication circuits.
dedicated backup
A dial backup module (DBM) assigned to a particular DSU that is continually
available for service restoral. The DBM switches to Dial Backup mode
automatically if the router detects data errors; no switching is required.
Diagnostic Control Panel
(DCP)
The face of the Model 3615 DualFlow DSU that continuously provides status
information about the DSU’s operation and allows an operator to manage its
operation. This is a generic term used for both the standalone and carrier-mounted
DSU models. See shared diagnostic control panel (SDCP) for the Model 3615
DualFlow DSU.
dial string
A sequence of up to 36 characters that the DBM can send into the dial network to
establish a call to a remote backup device. It consists of a telephone number and
may include other information, such as a callback directory pointer.
DIP switch
Dual In-line Package switch.
Direct Distance Dialing
(DDD)
Telephone exchange service, the Public Switched Telephone Network (PSTN or
dial network) that enables a telephone service user to access telephone lines without
operator assistance.
DMI
Data Mode Idle. Refers to a sequence of 1s transmitted or received on the DDS or
Switched 56 kbps network. When the DSU Port and DBM Port branch
configuration option RTS Cntrl is set to FrcOn, the DSU will transmit DMI
whenever RTS is Off. Data Mode Idle operation is recommended for point-to-point
applications. and is also used for Switched 56 kbps call set up signaling.
DSR
The state of the Data Set Ready lead (V.24 circuit 107).
DTR
The state of the Data Terminal Ready lead (V.24 circuit 108).
errored second
A performance measurement reported during a Digital Test that is defined as a
second in which at least one error has been detected.
Facility Alarm
(FA)
A failure condition reported to the NMS when there is a break in communication
with one or more tributary.