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

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363-206-285
Circuit Pack Descriptions
Issue 3 June 2001 7-33
Control Functions 7
The major control functions of the DS1 circuit pack are as follows:
■
Protection switching for MXRVO/STS1E circuit pack protection
■
VT path overhead processing
■
Internal fault detection
■
Inventory information ( CLEI code, date of manufacture, etc.).
Maintenance Signal Functions 7
The major maintenance signal functions are as follows:
■
Detects VT path AIS
■
Inserts DS1 AIS toward fiber and toward DSX-1
■
Inserts and detects VT path yellow signal.
BBF3/BBF3B DS1PM Circuit Pack Description 7
Purpose of Circuit 7
The DS1PM circuit pack provides all of the functions of a BBF1B circuit pack and
also provides performance monitoring (PM) of SF and ESF signals to allow for T1
tariff verification. For PM, the DS1 signals from the DSX are monitored; PM data
from the opposite direction is provided by accessing the ESF data link. The new
BBF3B has the additional capability of allowing single DS1 facility loopbacks.
DS1PM Faceplate Indicator 7
The DS1PM circuit pack FAULT indicator is shown in Figure 7-12. This red FAULT
LED is lit by the SYSCTL on detection of a DS1PM circuit pack failure. In the
event of an incoming signal failure, this LED flashes on and off.