Why do some communication standards use 8b/10b encoding?

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    Question: Why do some communication standards use 8b/10b encoding?

     

    Answer:

    8B/10B encoding ensures the correct function of the link by providing the following:
    - A minimum transition density to allow the serial receive PLL to extract a clock from the data stream.
    - A DC-balance in the signaling to reduce data baseline wander
    - Run-length limits in the serial data to limit the bandwidth of the serial link
    - A means of framing the remote receiver