← Back to Labs
TCP Three-Way Handshake
Step through the full TCP lifecycle: connect, exchange data, and close
Client
CLOSED
Server
LISTEN
SYN
▶
SYN-ACK
◀
ACK
▶
data exchange
FIN
▶
ACK
◀
FIN
◀
ACK
▶
Step 1 / 9Ready to Connect
The server is listening on port 80, waiting for incoming connections. The client has a socket ready but has not attempted to connect yet. Think of it like dialing a phone number: the other end is already waiting for the call.
Arrow keys to navigate · R to reset
Tap dots to jump to any step