Two enterprise networks must be connected together. Both networks are using the same private IP addresses. The client requests from both sides should be translated using hide NAT (dynamic NAT) with…

A single Cisco IOS router is fully capable of performing bidirectional dynamic NAT using the ip nat inside source and ip nat outside source commands together, making two routers unnecessary.

Configuring ip nat inside and ip nat outside on the interfaces is required but is only the interface-level prerequisite; without two separate pools and source statements, overlapping addresses cannot be correctly translated in both directions.

The overload keyword must be explicitly appended to the ip nat inside source or ip nat outside source statement; PAT overload is not enabled by default in Cisco IOS NAT configuration.

Cisco IOS supports simultaneous ip nat inside source and ip nat outside source statements on a single router, enabling translation in both directions. Two distinct NAT pools must be used so that each translation domain maps to a unique non-overlapping address range, allowing the router to correctly identify and reverse-translate return traffic for both sides.

NAT Virtual Interface (NVI) uses a single interface model that removes the inside/outside distinction, but it does not by itself resolve the requirement for two separate pools to handle bidirectional translation of overlapping address spaces.