This image describes a human protocol side-by-side with a computer network protocol. The human protocol is represented by two heads facing each other with vertical lines stretching downward from each, representing time. Each protocol interaction appears as a diagonally descending blue arrow from one side to the other as each person speaks, and their conversation proceeds as:

Hi

Hi

Got the time?

2:00

The computer network protocol appears similarly, replacing the heads of people with a desktop computer on the left and a server tower on the right. Their conversation proceeds as:

TCP connection request

TCP connection reply

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