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Gazettabyte - Home - Microchip launches the first terabit physical layer device
Other features the Meta-DX1 supports besides MACsec encryption include gearbox functionality that translates between 10 and 25 gigabits non-return-to-zero (NRZ), and between 25-gigabit NRZ and 56-gigabit 4-level pulse-amplitude modulation (PAM-4).
Having the gearbox function on-chip allows a high-capacity switch chip that uses 56-gigabit PAM-4 signals to talk to a 100-gigabit QSFP28 optical module, for example.
