Finalizing with an ACK packet

Frame 3 is the final packet in the three-way handshake. At this point, the sequence and acknowledgment numbers are as follows:

  • Sequence number: 1 (relative sequence number)
  • Acknowledgment number: 1

To see the details, go to frame 3 and then to the TCP header, and then expand the TCP flags, which are now set at ACK, as shown in the following screenshot: 

TCP ACK flag set

In addition, we also see Transmission Control Protocol (tcp), 32 Bytes, in the status bar along the bottom, as shown in the preceding screenshot. Again, this is because this connection has TCP options, which adds to the length of the TCP header. ...

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