Stateful Firewalling: A network communication is made up of small chunks of data called packets. In the case of TCP, several of these packets are used solely to create, maintain, and finish the connection. This is because TCP uses the concept of a connection, allowing it to automatically correct data errors, interpret incoming packets in the same order they were sent in, and otherwise keep track of a sustained connection. Now, how does this relate to packet filters (firewalls)? Normal...