Applied Network Security

The TCP three way handshake

If you don't already know what the TCP three way handshake then here's a simple explanation. When a host device (such as your computer) attempts to communicate with a server with reliable connection because it needs to error check and be capable of reestablishing the connection then likely it will choose the TCP protocol over UDP (which is connectionless). Let's go over some basics for a moment and look into what a successful handshake would look like. First a host, such as your computer, initiaties a TCP connection by providing a TCP SYN packet to the destination host (let's just say it's a file sharing server for this example). After the server receives the TCP SYN it returns to a packet back in response with ...