TCP 3 Way Handshake – TCP/IP 101

TCP 3 Way Handshake – TCP/IP 101

TCP 3 Way Handshake - TCP IP 101 Client try to resolve the name  -DNS -take destination IP server and netmask to determine if is local or remote host.

If local connect directly

If remote connect first to gateway

1. initial SYN pack..hey server is my client…are u there? I like to get in port 80. That’s the properly TCP address

SYN .5:55001 –> .8:80

2.SYN/ACK .8:80  <– .5:55001  yeaaa I’m here  TCP stack swap the source in destination

client receive

3. ACK .5:55001 –> .8:80

TCP 3 Way Handshake - TCP IP 101 2

All devices in between the client and server recognized the TCP /IP – including firewall

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