Where is the logic of the TCP protocol implemented?

Question

Computer networks

Consider the following:
1) host A sends a data segment to host B
2) host B does NOT receive the data and does NOT send an acknowledgment to host A
3) host A does NOT receive an acknowledgment
4) host A resends the data segment to host B
5) host B receives the data and sends an acknowledgment to host A
6) host A receives an acknowledgment
Which "part of host A" decides to resend the data? LAN card? Network card driver? Operating system (kernel of the operating system)?

Answer 1

OS, of course,
there is also a control code, in different OS it is calculated differently,
which Kevin Mitnick allegedly picked up
+ classic port antiscan - with a response delay, too OS