The Acknowledgement number contains the next sequential number of the byte of data the sender of the packet expects to receive, that is the next expected TCP octet.

Data Offset indicates the number of 32-bit words in the TCP header.

The Reserved field is reserved for future use.

Flags contains control information such as setup and termination of a session.

The Window field specifies the sender's window or buffer size for incoming data.

Urgent Pointer points to the first urgent data byte in the packet.

The Options field specifies various TCP options. For example, you can indicate the maximum TCP segment size.

The Data field contains information to be used by upper-layers or applications.
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