Understand TCP 3 way handshake!

What is TCP 3 way handshake?

What is TCP. TCP means transmission control protocol, in short, this is a protocol to transmit data after a connection is made. You use TCP when you request a website for example. The handshake is what happens behind the scene. This is how you establish a connection before transmitting data.

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Here it how it works!

When you request a website, your computer (client) will first send a packet with a SYN flag to the web server. SYN is short for SYNchronize. It's an attempt to open a connection. The server then respond with SYN flag and ACK flag to ACKnowledge the connection. Then your computer sends an ACK flag to confirm the handshake

After the handshake is completed, the connection is open and the computer starts sending the data!

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You can compare this to two persons starting a conversation.

first person: Hi, do you want to talk (SYN)
second person: Sure let's talk (SYN, ACK)
first person: Ok let's talk (ACK)

Then the conversation starts (data transfer)!

You will need this concept for the hacking series https://steemit.com/hack/@pierlave/learn-hacking-1-00-overview
This is a simplified explanation of how the handshake works, if you want more details or have any questions, feel free to ask!

@pierlave

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