What is a TCP segment?


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What is a TCP segment?

A TCP segment is a unit of data transferred between sessions connected by TCP.

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Find the size of a TCP segment

  • TCP payload segment size = (Total Length of IP Header)-(Header Length of IP Header)-(Header Length of TCP Header)

TCP segment size issues

  • The size of the TCP segment is directly related to the performance problem of the TCP connection line.
  • If the size of the TCP segment is too small, the data capacity will be small, and frequent transmission will occur, making it inefficient.
  • Conversely, if the size of the TCP segment becomes too large, it becomes more than the size of MTU, and IP fragmentation occurs, making it inefficient. (Frequent fragmentation is inefficient)

What is the proper size of the TCP segment?

  • min (transmission buffer size, reception buffer size, MTU size, path MTU size)-header size
  • In general, it is common to see the size of the same receive buffer as the TCP module as a limit.

Reference

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