Glossary
GL-4
7110-A2-GB20-00
June 1997
Loss of Frame. The inability to maintain frame synchronization.
Loss of Frame Count. A count of the number of LOFs declared.
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.
Loss Of Signal. The T1 line condition where there are no pulses.
Line Signal Detect. An EIA-lead standard for V.24 circuit CT 109; an output signal
(DCE-to-DTE).
The device that queries agents for management information, or receives unsolicited SNMP
trap messages indicating the occurrence of specific events.
Management Information Base. The set of variables a device running SNMP maintains.
Standard, minimal MIBs have been defined, and vendors often have private enterprise
MIBs. In theory, any SNMP manager can talk to any SNMP agent with a properly defined
MIB. MIB-II refers to an extended management database that contains variables not
defined in the original MIB I.
A method for interleaving several access channels onto a single circuit for transmission
over the network.
The T1 network interface connector on the rear panel of the DSU/CSU.
Network Management System. A computer system used for monitoring and controlling
network devices.
A connection or switching point on the network.
No Signal. A network-reported condition.
A specific item within the Management Information Base (MIB).
Out Of Frame. An error condition in which frame synchronization bits are in error. A
network-reported condition.
Out of Service. A digital network trouble signal.
A data network circuit with one control and one tributary device.
Point-to-Point Protocol. A link-layer protocol used by SNMP.
The rules that govern how devices exchange information on a network. It covers timing,
format, error control, and flow control during data transmission.
Public Switched Telephone Network. A network shared among many users who can use
telephones to establish connections between two points.
Quasi-Random Signal Source. Test pattern that approximates live data that can be
monitored for logic errors (on the network and the data port).
A reinitialization of the device that occurs at power-up or in response to a reset command.
Request for Comments. The set of documents that describes the standard specifications
for the TCP/IP protocol suite.
Routing Information Protocol. Specifies the routing protocol used between DSUs.
Receive Line Signal Detect. See CD.
A device that makes decisions about the paths network traffic should take and forwards
that traffic to its destination. A router helps achieve interoperability and connectivity
between different vendor’s equipment, regardless of protocols used.
LOF
LOFC
loopback
LOS
LSD
manager (SNMP)
MIB
multiplexing
network interface
NMS
node
NS
object (SNMP)
OOF
OOS
point-to-point circuit
PPP
protocol
PSTN
QRSS
reset
RFC
RIP
RLSD
router