Lucent Technologies Metropolis DMXplore, Руководство по установке

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G L O S S A R Y
G L - 2 5
365-372-334 R2.0
Issue 4, November 2004
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OC-3c (STS-3c)
Optical Carrier Level 3 Concatenated Signal. Low-speed broadband equivalent to
three STS-1s linked together with a single path overhead.
OC-12
Optical Carrier Level 12 Signal (622 Mb/s).
OC-12c (STS-12c)
Optical Carrier Level 12 Concatenated Signal. High-speed broadband equivalent
to twelve STS-1s linked together with a single path overhead.
OC-48
Optical Carrier Level 48 Signal.
Operations Interface
Any interface that provides information on the system performance or control.
These include the equipment LEDs, SYSCTL faceplate, and office alarms.
OS - Operations System
A central computer-based system used to provide operations, administration, and
maintenance functions.
OSI - Open Systems Interconnection
Referring to the OSI reference model, a logical structure for network operations
standardized by the Internation Standards Organization (ISO).
P Pass Through
Paths that are cross-connected directly across an intermediate node in a ring
network.
Plesiochronous Network
A network that contains multiple maintenance subnetworks, each internally
synchronous and all operating at the same nominal frequency, but whose timing
may be slightly different at any particular instant. For example, in SONET
networks, each timing traceable to their own Stratum 1 clock are considered
plesiochronous with respect to each other.
PM - Performance Monitoring
Measures the quality of service and identifies degrading or marginally operating
systems (before an alarm would be generated).
Port
The physical, electrical, or optical interface on a system. For example, DS1, DS3,
OC-3, and OC-12. See Channel.