In Cisco terminology, Port Address Translation is commonly referred to by which other NAT feature name that describes many inside addresses sharing a single public IP?

Introduction / Context:
Port Address Translation, or PAT, is a very common form of NAT that allows many internal devices to share a small number of public IP addresses, often just one. Cisco documentation and exam questions often use a specific term for this feature that emphasises how multiple inside addresses are mapped to a single global address by overloading it with different port numbers. Recognising this synonym is important for correctly interpreting configuration guides and exam scenarios.

Given Data / Assumptions:

PAT maps multiple inside local addresses to one or a few inside global addresses by using different source port numbers.

Cisco IOS implements this behaviour with the overload keyword in NAT configuration.

The question asks specifically what PAT Address Translation is also called in Cisco terminology.

Only one option matches the widely used term in Cisco training material.

Concept / Approach:
When you configure ip nat inside source list 1 interface serial0 overload or ip nat inside source list 1 pool Corp overload, the overload keyword enables many to one translation using port numbers. This is exactly how PAT works. Because of this overload keyword, Cisco often refers to PAT as NAT Overload. In many training texts, the phrases PAT and NAT Overload are used almost interchangeably.

Step-by-Step Solution:
Recall that static NAT creates a one to one mapping and is not called PAT. Dynamic NAT with a pool creates many to many mappings without reusing addresses by ports; this is still not PAT. PAT specifically allows many internal addresses to share one global address by using port numbers, and is configured with the overload keyword. The presence of overload in configuration syntax leads to the descriptive name NAT Overload for this type of translation. Among the options, NAT Overload is the only one that matches this widely recognised name.

Verification / Alternative check:
Looking at Cisco examples, you will often see explanatory comments such as ip nat inside source list 1 interface serial0 overload, which is called NAT Overload or PAT. Books and official training material repeatedly state that NAT overload is the Cisco term for PAT. This confirms that NAT Overload is the correct synonym.

Why Other Options Are Wrong:
Option a, NAT Fast, is not a standard term for any NAT feature and appears only as a distractor.

Common Pitfalls:
Option b, NAT Static, refers to static one to one mappings, which do not multiplex many hosts behind a single address and do not use port overloading.
Option d, Overloading Static, combines words in a way that does not match any official Cisco feature name.
Option e, Port Forwarding, is related to static NAT or translation of specific ports for inbound traffic, but it is not the same concept as PAT for outbound sessions.

Common Pitfalls:
A frequent misunderstanding is to treat all NAT features as the same and ignore the differences between static NAT, dynamic NAT and PAT. In practice, PAT or NAT Overload is the most widely deployed form for home and small office Internet access, because it conserves public addresses. Remember that any NAT configuration using the overload keyword is implementing PAT or NAT Overload.

Final Answer:
PAT Address Translation is also called NAT Overload in Cisco terminology.