Lucent Technologies DDM-2000 OC-3, User & Service Manual

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363-206-285
Circuit Pack Descriptions
7-52 Issue 3 June 2001
HDSL Quick Reference Summary 7
Transmission Functions 7
Major transmission functions of the HDSL circuit pack are as follows:
■
Multiplexes four VT1.5 SPEs to a byte-interleaved VT-G signal
■
Provides the VT-G signal to a MXRVO/STS1E circuit pack
■
Inserts VT path overhead
■
PairGain compatible, 4-wire HDSL
■
Bi-directional transmission port of 1.544 Mb/s over twisted pair
■
Loopback options
■
Receives up to two HDSL formatted signals
■
Receives a SONET VT-G clock and frame synchronizing signals from its
associated MXRVO/STS1E
■
Demultiplexes the VT-G into four VT1.5 signals
■
Terminates VT path and the embedded DS1 signal from each VT1.5 SPE
■
Desynchronizes the DS1 signals and maps directly into PairGain HDSL
■
Provides HDSL to VT1.5 mapping
■
Recovers DS1 clock and NRZ data from each HDSL payload
■
Synchronizes and maps each data signal to a VT1.5 SPE.
Control Functions 7
The major control functions of the HDSL circuit pack are as follows:
■
Protection switching for MXRVO/STS1E circuit packs
■
VT path overhead processing
■
Internal fault detection
■
Inventory information (
CLEI
code, date of manufacture, etc.)
■
Monitors a DS1 signal with SF or ESF frame format and generates PM
data
Maintenance Signal Functions 7
The major maintenance signal functions are as follows:
■
Monitors DS1 signal for near-end and far-end performance
■
Detects VT path AIS
■
Inserts DS1 AIS toward fiber and far-end HDSL equipment