
nrt-VBR
Non Real-Time Variable Bit Rate
NRZ
Non Return to Zero code
NSAP
Network Service Access Point
NTP
Network Time Protocol
A.15 O
OA
OADM
OAM
Operations, Administration and Maintenance
OAM auto-discovery
In the case of OAM auto-discovery, two interconnected ports, enabled with the Ethernet
in the First Mile OAM (EFM OAM) function, negotiate to determine whether the mutual
EFM OAM configuration match with each other by sending and responding to the OAM
protocol data unit (OAMPDU). If the mutual EFM OAM configuration match, the two
ports enter the EFM OAM handshake phase. In the handshake phase, the two ports
regularly send the OAMPDU to maintain the neighborhood relation.
OCP
ODF
ODU
Outdoor Unit
OFS
Out-of-frame Second
OHA
Overhead Access Function
OLT
Optical Line Terminal
Online Help
The capability of many programs and operating systems to display advice or instructions
for using their features when so requested by the user.
ONU
Optical Network Unit
OOF
Out of Frame
Optical Add/Drop
Multiplexer
A device that can be used to add the optical signals of various wavelengths to one channel
and drop the optical signals of various wavelengths from one channel.
Optical Amplifier
Devices or subsystems in which optical signals can be amplified by means of the
stimulated emission taking place in a suitable active medium.
Optical attenuator
A passive device that increases the attenuation in a fiber link. It is used to ensure that the
optical power of the signals received at the receive end is not extremely high. It is
available in two types: fixed attenuator and variable attenuator.
Optical Channel
Protection
In an optical transmission link that contains multiple wavelengths, when a certain
wavelength goes faulty, the services at the wavelength can be protected if the optical
channel protection is configured.
Optical Connector
A component normally attached to an optical cable or a piece of apparatus to provide
frequent optical interconnection/disconnection of optical fibers or cables.
Optical Distribution
Frame
A frame which is used to transfer and spool fibers.
OptiX OSN 550 Multi-Service CPE Optical Transmission
System
Configuration Guide
A Glossary and Acronyms
Issue 02 (2011-06-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
A-21