- Mia
Harry Collins
Answered on 8:14 am
For 100G mode with QPSK modulation, the FEC type could be oFEC (OpenROADM) or SDFEC (Soft Decision FEC) with probabilistic constellation shaping.
For 200G mode with QPSK modulation, the FEC type could be SDFEC with probabilistic constellation shaping.
For 400G mode with 16-QAM modulation, the FEC type could be SDFEC with probabilistic constellation shaping.
The 400G-BIDI module can work in different ways depending on the switch and the application. It can use different types of FEC (Forward Error Correction) to improve the signal quality. FEC is a method of adding extra bits to the data to detect and correct errors.
One way is to use the 400G-SR4.2 or 4x 100G-SR1.2 mode, where the switch does the FEC and the module does not. The FEC used here is called KP-FEC, which is a type of Reed-Solomon FEC.
Another way is to use the 4x 100G-BIDI (100G-SRBD) mode, where the module does the FEC and the switch does not. The module uses a different FEC for each pair of fibers, which can work with the existing 100G-BIDI modules. This way, you can keep using your old 100G-BIDI modules with the new 400G-BIDI modules.
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