A Good "Deal"! In modern systems $($TCP$/$IP running over Ethernet and WiFi$),$ just $3$ pairs of numbers can guide our packets across the world: they make fast local$-$delivery switched networks, and globally$-$scalable routed networks, possible. Imagine a client $($source$)$ is requesting an IoT$-$related service from a server $($destination$),$ so the communication is starting from the client. Please match the relevant number with its description.