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Variants of the CSMA/CD protocols

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• Non-persistent CSMA/CD:
  • Recall the non-persistent CSMA protocol:

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  • When we use the non-persistent CSMA backoff algorithm in the CSMA/CD flow chart:

    we obtain the Non-persisten CSMA/CD protocol:

    Note:

    τ = the end-to-end-delay

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  • We can simplify the previous flow chart:

    to this:

    (The non-persistent CSMA/CD protocol)

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• 1-persistent CSMA/CD:
  • Recall the 1-persistent CSMA protocol:

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  • When we use the 1-persistent CSMA backoff algorithm in the CSMA/CD flow chart:

    we obtain the 1-persisten CSMA/CD protocol: