CS138-lecture-20210401

Connection oriented transport: TCP #

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Entire header size is \( 32 \text{ bits } \cdot 5 = 160 \text{ bits } = 20 \text{ bytes } \) . The receive window is used for flow control.

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Sequence number example:

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Both sides randomize the sequence number they will use at the beginning.

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Reliable data transfer #

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Flow control #

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The difference between flow control and congestion control:

  • Flow control is to make sure the receiver is not overwhelmed
  • Congestion control is to make sure that the road (routers, other resources) is not overwhelmed

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