Sequencing and acknowledging data

Because TCP is a connection-oriented protocol, the operating system keeps track of every byte (or octet) of data. Each byte is sequenced and, once received, is acknowledged. The following are the fields that help provide a snapshot of the data that's exchanged during a TCP connection:

  • Sequence number 32-bit: The three-way handshake starts the sequencing. The Synchronization (SYN) packets found in the first two packets of the three-way handshake are responsible for synchronizing the sequence numbers that are used during the connection. For example, as shown in the following screenshot, a client sends a SYN packet to the server with a sequence number of 100. The server responds by sending a Synchronization  ...

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