
Current Performance
Data
Performance data stored currently in a register. An NE provides two types of registers,
namely, 15-minute register and 24-hour register, to store performance parameters of a
performance monitoring entity. The two types of registers stores performance data only
in the specified monitoring period.
Cyclic Redundancy
Check
A procedure used in checking for errors in data transmission. CRC error checking uses
a complex calculation to generate a number based on the data transmitted. The sending
device performs the calculation before transmission and includes it in the packet that it
sends to the receiving device. The receiving device repeats the same calculation after
transmission. If both devices obtain the same result, it is assumed that the transmission
was error free. The procedure is known as a redundancy check because each transmission
includes not only data but extra (redundant) error-checking values.
A.5 D
Data Communication
Network
A communication network used in a TMN or between TMNs to support the data
communication function.
Digital Data Network
A high-quality data transport tunnel that combines the digital channel (such as fiber
channel, digital microwave channel, or satellite channel) and the cross multiplex
technology.
DC
Direct Current
DCC
Data Communication Channel
DCD
Data Carrier Detect
DCE
Data Circuit-terminal Equipment
DCN
DDF
DDN
Defect
A limited interruption in the ability of an item to perform a required function.
Delay Measurement
The time elapsed since the start of transmission of the first bit of the frame by a source
node until the reception of the last bit of the loopbacked frame by the same source node,
when the loopback is performed at the frame's destination node.
Demultiplexing
A process applied to a composite signal formed by multiplexing, for recovering the
original independent signals, or groups of these signals.
Device set
A collection of multiple managed devices. By dividing managed devices into different
device sets, users can manage the devices by using the U2000 in an easier way. If an
operation authority over one device set is assigned to a user (user group), the authority
over all the devices in the device set is assigned to the user (user group), thus making it
unnecessary to set the operation authority over all the devices in a device set separately.
It is recommended to configure device set by geographical region, network level, device
type, or another criterion.
Differentiated Services
Code Point
A marker in the header of each IP packet that prompts network routers to apply
differentiated grades of service to various packet streams. It is specified by the DiffServ
policy proposed by the IETF (Internet Engineering Task Force). This allows Internet and
other IP-based network service providers to offer different levels of service to customers.
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.
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