Glossary
GL-2
7924-A2-GB20-30
October 1997
Federal Communications Commission. Board of Commissioners that regulates all U.S.
interstate, intrastate, and foreign electrical communication systems that originate from the
United States.
Far End Bit Error. Number of errors reported by the remote equipment.
High Density Bipolar 3 coding format.
High-bit-rate Digital Subscriber Loop. Provides high bandwidth, bi-directional transmission
over copper wire for both T1 and E1 services.
Host Termination Unit. A generic reference to either an HTU-C or HTU-R module.
Host Termination Unit – Central. The module at the CO (central office) or central site end
of an HDSL connection. Also known as a Network Termination Unit (NTU).
Host Termination Unit – Maintenance. A carrier–mounted module used to perform
maintenance operations on one or more HTU-R and HTU-C modules.
Host Termination Unit – Remote. The module at the CP (customer premises) end of an
HDSL connection. Also known as a Line Termination Unit (LTU).
Light Emitting Diode. A status indicator that responds to the presence of a certain
conditions.
Used to test various portions of a data link in order to isolate an equipment or data line
problem. A diagnostic procedure that sends a test message back to its origination point.
Multiframes Out of Sync. A performance statistic that counts the number of multiframes
received out of sync.
Out Of Frame. An error condition in which frame synchronization bits are in error. A
network-reported condition.
A reinitialization of the device that occurs at power-up or in response to a reset command.
Request to Send. An EIA-lead standard for V.24 circuit CT 105; an input signal
(DTE-to-DCE).
Received Data. An EIA-lead standard for V.24 circuit CT 104; an output signal
(DCE-to-DTE).
A data signaling rate common in the United States. A term for a digital carrier facility used
to transmit a DS1 formatted signal of 1.544 Mbps.
Transmit Data. An EIA-lead standard for V.24 circuit CT 103; an input signal
(DTE-to-DCE).
ITU-T standard for a high-speed, 34-pin, DCE/DTE interface.
FCC
FEBE
HDB3
HDSL
HTU
HTU-C
HTU-M
HTU-R
LED
loopback
MOS
OOF
reset
RTS
RXD
T1
TXD
V.35
