R3166-R3206-HP High-End Firewalls Network Management Configuration Guide-6PW101

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IP routing overview
Routing in the Internet is achieved through routers. Upon receiving a packet, a router determines the
optimal route based on the destination address and forwards the packet to the next router in the path.
When the packet reaches the last router, it then forwards the packet to the destination host.
Routing tables play a key role in routing. Each router maintains a routing table, and each entry in the
table specifies a physical interface that packets destined for a certain address should go out to reach the
next hop—the next router—or the directly connected destination.
Routes in a routing table can be divided into three categories by origin:
• Direct routes—Routes discovered by data link protocols, also known as “interface routes”
• Static routes—Routes that are manually configured
• Dynamic routes—Routes that are discovered dynamically by routing protocols