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

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363-206-285
Circuit Pack Descriptions
7-140 Issue 3 June 2001
26G2-U OLIU Quick Reference Summary 7
Transmit Functions 7
Major transmit functions of the 26G2-U OLIU circuit pack are as follows:
a. Selects and multiplexes VT-Gs into one STS-1 synchronous payload
envelope (SPE).
b. Adds SONET and STS-1 path transport overhead
c. Scrambles the STS-1 signal to prepare for optical conversion
d. Uses a laser transmitter to produce a SONET standard OC-1 optical signal.
Receive Functions 7
The following are major receive functions of the 26G2-U OLIU circuit pack:
a. Receives one SONET standard OC-1 optical signal and converts it to an
electrical STS-1 signal
b. Extracts transport and STS-1 path overhead
c. Processes the STS-1 pointer and frame-synchronizes the STS-1 signals
d. Processes the VT1.5 pointers and frame-synchronizes the VT1.5 signal
e. Provides path protection switching
f. Provides VT1.5/STS-1 signal cross-connections
g. Sends VT-Gs to the DS1 circuit packs
Control Functions 7
The major control functions are as follows:
a. Processes transport and path overhead
b. Stores inventory information ( CLEI code, date of manufacture, etc.)
c. Supports VT and OC-1 signal degrade protection switching.
d. Supports protection switching of circuit packs in the low-speed slots.
Maintenance Signal Functions 7
The major maintenance signal functions are as follows:
a. Inserts and detects OC-1 line and STS-1 and VT1.5 path AIS
b. Inserts STS-1 and VT1.5 path unequipped signal
c. Inserts and detects line far-end-receive failure (FERF)
d. Inserts and detects STS-1 path yellow.