The Sushi Man Requires You're Help

Hi guys, i seem to have encountered a problem. I want to plug my somputer straight into my cable feed. Without going through a router. Problem is, when i do so, i dont get a connection. Look at attached scribbling for my setup. When i switch the blue cable (My computer) with the green one, i should be pluged right in, but apparently not. Please help, i really need to connect without a firewall.