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Optical Line Card
Overview :
An Optical Line Card is a tributary to a combined optical pipe where the
client NE is input over a fiber pair at a fixed wavelength, the data is
encoded/decoded, and output on a specific ITU grid wavelength via a fiber pair.
The core subsystems include:
- SR/IR MSA
- Short Reach/Intermediate Reach Multi-Source Agreement module is an
integrated subsystem including CDR/SERDES. Analog and digital signals, as well
as an I2C buss, are provided for monitoring, setpoints, control signals, and
alarms.
- FEC
- Forward Error Correction is the bidirectional processing path for the SONET
span its NE terminates. Modern devices include a rate change PLL and VCO.
- LR/ULR MSA
- Long Reach/Ultra Long Reach module is the optical interface out to the
combined pipe. Internal structure similar to the SR/IR module.
- Processor
- Reads/writes the SONET header and controls setup and operation of the FEC
chip, handles MSA control/monitoring functions, and I/F to shelf controller
via B/P.
- Power
- Hot Swap controller provides inrush limiting, DC-DC converters provide
system power either as a multi-output converter or as point-of-load converters