How does NAT overload (PAT) relate to inbound connections from the internet?

• A. Inbound connections do not require any port forwarding or translation.
• B. Inbound connections initiated from the internet require port forwarding; otherwise, traffic may be blocked.
• C. PAT automatically opens all inbound ports.
• D. PAT prevents any inbound traffic.

Answer: (B)

PAT translates each internal device’s outbound connection to a shared public IP plus a unique source port, letting many private hosts use one address. But inbound connections from the internet aren’t automatically directed to a specific internal device. The NAT device needs a rule that tells it which internal IP and port to deliver to for a given external port, otherwise there’s no matching destination. That’s why you must set up port forwarding (destination NAT) for inbound access to a particular internal server; without it, the traffic is blocked or dropped. The NAT’s job is outbound address/port translation, not opening random inbound doors.