Glossary
GL-6 3160-A2-GB21-80
March 1999
Internet Control Management Protocol. Internet protocol that allows for the generation of
error messages, tests packets, and information messages related to IP.
Identity branch of the DSU/CSU menu tree.
A shared boundary between functional units.
The worldwide internetwork, which predominantly uses the TCP/IP protocol.
An interconnected collection of networks (also called an internet).
Internet Protocol address. The address assigned to an internet host.
International Standards Organization.
International Telecommunications Union. The telecommunications agency of the United
Nations, established to provide standardized communications procedures and practices.
Before March 1993 it was called CCITT.
Kilobits per second. One kilobit is usually taken to be 1,024 bits.
Local Area Network. A privately owned and administered data communications network
limited to a small geographic area.
Line Build-Out. The amount of attenuation of the transmitted signal that is used to
compensate for the length of wire between the transmitter and the receiver.
Liquid Crystal Display. Thin glass plates containing liquid crystal material. When voltage is
applied, the amount of light able to pass through the glass plates is altered so that
messages can be displayed.
Link Control Protocol.
Light Emitting Diode. A light or status indicator that glows in response to the presence of a
certain condition (e.g., an alarm).
The protocol that regulates the communication between two network nodes.
A trap that identifies the condition of the communications interface (linkDown or linkUp
traps).
Line LoopBack. A test in which the received signal on the network interface is looped back
to the network without change.
Loss of Frame. Occurs when a DS1 terminal is unable to synchronize on the DS1 signal
for some interval.
Loss Of Frame Count. The number of LOFs declared.
A test that verifies a device’s operation by connecting the device’s output to the device’s
input.
Loss of Signal. The T1 line condition where there are no pulses.
Local Loopback branch of the DSU/CSU menu tree.
Link Quality Reports.
The device that queries agents for management information, or receives unsolicited
messages (traps) indicating the occurrence of specific events.
The master timing source used to synchronize all of the T1 and data port interfaces on the
DSU/CSU.
Megabyte or megabytes. A unit of memory measurement equal to approximately one
million bytes (typically 1,048,576 bytes).
ICMP
ID branch
interface
Internet
internetwork
IP address
ISO
ITU
kbps
LAN
LBO
LCD
LCP
LED
link layer protocol
link trap
LLB
LOF
LOFC
loopback test
LOS
Lpbk branch
LQR
manager (SNMP)
master clock
MB