TCP 3-Way Handshake sequence is:

Step 1: The initiating host sends a packet with no data to the target host with a SEQ=1 and sets the SYN flag to 1.

Step 2: The target host responds with a packet with ACK=2, SEQ=8, and the SYN and ACK flags set to 1.

Step 3: The initiating host sends a packet with SEQ=2, ACK=9, and the ACK flag set to 1.

Step 4: A normal-controlled connection is established.

References: https://en.wikipedia.org/wiki/Transmission_Control_Protocol https://www.cisco.com/c/en/us/support/docs/ip/routing-information-protocol-rip/13788-3.html