Understand the concept
Routers forward packets between IP networks. A routing table selects a next hop based on destination prefix, longest-prefix matching, and applicable route-selection rules.
OSPF is a link-state routing protocol; its path selection uses interface cost. NAT changes address information, while PAT can distinguish many inside sessions using ports.
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Practice task
Use show commands in a lab to compare connected, static, and OSPF-learned routes, then trace traffic end to end.
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