Glossary
3160-A2-GB24-10 March 2001 GL-7
Mbps Megabits per second. One megabit is 1,048,576 (10242)bits.
menu tree The structure containing the menu hierarc hy star ting at a Top-Level menu and extending
down to various device functions.
MIB Management Information Base. A database of managed objects used by SNMP to provide
network management information and device control.
MIB II MIB Release2. The current Internet-standard MIB, defined by RFC 1213.
module A compact assembly functioning as a component in a larger system or unit.
MRU Maximum Request Unit.
network A configuration of data processing devices used for information exchange.
network interface The T1 network interface connector on the rear panel of the DSU/CSU.
NMS Network Management System. A computer system used for monitoring and controlling
network devices.
node A connection or switching point on the network.
object (SNMP) A specific item within a Management Information Base (MIB).
OOF Out Of Frame. An error condition in which frame synchronization bits are in error .
option A hardware or software function that can be selected or enabled as part of a configuration
process.
PAP Password Authentication Protocol. A security technique that requires a user password for
access to a system.
parity A way of checking data accuracy by counting the number of bits that have a value of one.
PBX Private Branch Exchange. Telephone switching equipment dedicated to one customer. A
PBX connects private telephones to each other and to the public dial network.
PC Personal Computer.
PDU Protocol Data Unit. A message containing protocol-specific information.
PDV Pulse Density Violation. The number of ones (marks, pulses) is not adequate for the line
requirement.
Perf branch Performance Report branch of the DSU/CSU menu tre e.
PLB Payload Loopback. Loopback mode that loops the information received on the T1 network
interface back to the network after it has passed through receive and transmit framing
section.
PORT (1–4)
interface The synchronous data port interface on the DSU/CSU.
POWER connector The power input connector on the DSU/CSU.
power-on self-test A test that checks most hardware components when power is applied to the device or a
reset is initiated.
PPP Point-to-Point Protocol. A protocol for packet transmission over serial links, specified by
Internet RFC1661.
PRBS Pseudo-Random Bit Sequence. A test pattern containing any possible combinat ion of digital
ones and zeros for a given string length.