GL-1
7975-A2-GB20-40
December 1998
Glossary
Alternate Mark Inversion. A line coding technique used to accommodate the ones density
requirements of E1 or T1 lines.
Asynchronous Terminal Interface. A menu-driven, VT100-compatible system for
configuring and managing the termination unit.
Bipolar Violation. In a bipolar signal, a one (mark, pulse) which has the same polarity as its
predecessor.
Any part of the local loop that is not in the direct talking path between the CO and the
service user.
Carrier Detect. The received line signal detector. V.24 circuit 109.
CO. The PSTN facility that houses one or more switches serving local telephone
subscribers.
Communications port. A computer’s serial communications port used to transmit to and
receive data from a modem. The modem connects directly to this port.
Customer Premises.
Customer Premises Equipment. Terminal equipment on the service user’s side of the
telecommunications network interface.
Central Processing Unit. The main or only computing device in a data processing system.
Cyclic Redundancy Check. A mathematical method of confirming the integrity of received
digital data.
Clear To Send. A signal indicating that the device is ready for the DTE to transmit data.
Usually occurs in response to Request To Send (RTS).
Code Violation. This is equivalent to a BPV. Used with HDB3 coding format.
Data Communications Equipment. The equipment that provides the functions required to
establish, maintain, and end a connection. It also provides the signal conversion required
for communication between the DTE and the network.
Data Channel Loopback. Loops the data received from the network interface, for all DS0
channels allocated to the selected port, back to the network.
Digital Subscriber Line. The non-loaded, local-loop copper connection between the
customer and the first node within the network.
Digital Subscriber Line Access Multiplexer. A platform for DSL modems that provides
high-speed data transmission over traditional twisted-pair wiring.
Data Set Ready. A signal from the modem to the DTE that indicates the modem is turned
ON and connected to the DTE.
Data Terminal Equipment. The equipment, such as a computer or terminal, that provides
data in the form of digital signals for transmission.
Data Terminal Loopback. Loopback mode that loops the data for a particular synchronous
data port back to the port just before it is combined with the rest of the T1 data stream.
AMI
ATI
BPV
bridged tap
CD
CO
COM port
CP
CPE
CPU
CRC
CTS
CV
DCE
DCLB
DSL
DSLAM
DSR
DTE
DTLB
