You are designing the routing design for two merging companies that have overlapping IP address space. Which of these must you consider when developing the routing and NAT design?

While outbound local-to-global NAT does occur after routing, this is the less critical design constraint for overlapping IP space because the routing lookup already uses the correct local address before any translation takes place.

In Cisco IOS NAT processing, for packets arriving from the outside (global-to-local direction), the NAT translation is applied first before the routing table is consulted, meaning the router makes its forwarding decision based on the post-translation local destination address. For merging companies with overlapping IP address space, this means the internal routing tables must contain routes for the translated local addresses rather than the original global addresses - otherwise packets will be dropped after translation due to no matching route. Misunderstanding this order leads to black-holed traffic that passes NAT but cannot be forwarded because the routing design was built around pre-NAT addresses.

Local-to-global NAT translation does not occur before policy-based routing - in Cisco IOS the routing phase including PBR is evaluated first for outbound traffic, and NAT translation is applied only after the forwarding decision is made.

Global-to-local NAT translation occurs before routing, not after policy-based routing - this statement inverts the actual Cisco IOS order of operations and would produce a fundamentally incorrect NAT and routing design for overlapping address spaces.