Finding out what the other computers are up to

Now that we have a better idea of the computer behind each IP address, we can begin to target the network traffic itself as it flows through our network.

For these experiments, we'll be using an application called Ettercap. The act of listening in on network traffic is commonly known as sniffing and there are several great sniffer applications to choose from. What sets Ettercap apart is its ability to combine man-in-the-middle attacks with network sniffing and a bunch of other useful features, making it an excellent tool for network mischief.

You see, one obstacle that sniffers have to overcome is how to obtain network packets that aren't meant for your network interface. This is where Ettercap's man-in-the-middle attack comes into play. We will launch an ARP poisoning attack that will trick any computer on the network into sending all its network packets through the Pi. Our Pi will essentially become the man in the middle, secretly...