in general the router uses the network address to compare to the routing table. Specifically, on the internet, the Router looks up the destination IP address in the router table to determine where to route the packet.
A router would then consult its tables to determine what the next router address should be, and the best route.
network portion of ip address
network portion of ip address
172.16.0.0
Routers
The network address
Usually the router.
First, routing is the process a router performs when making forwarding decisions for each packet arriving at the gateway interface. To forward a packet to a destination network, the router requires a route to that network. If a route to a destination network does not exist on the router, the packet will be forwarded to the default gateway. Now, the destination network can be a number of routers or hops away from the default gateway. If the router has an entry for the network in its routing table, it would only indicate the next-hop router to which the packet is to be forwarded to and not the exact route to the final router. To sum it up, the routing process uses a routing table to map the destination address to the next hop and then forwards the packet to the next-hop address.
First, routing is the process a router performs when making forwarding decisions for each packet arriving at the gateway interface. To forward a packet to a destination network, the router requires a route to that network. If a route to a destination network does not exist on the router, the packet will be forwarded to the default gateway. Now, the destination network can be a number of routers or hops away from the default gateway. If the router has an entry for the network in its routing table, it would only indicate the next-hop router to which the packet is to be forwarded to and not the exact route to the final router. To sum it up, the routing process uses a routing table to map the destination address to the next hop and then forwards the packet to the next-hop address.
router#config t router(config)#router eigrp 100 #net NETWORK ADDRESS
In a multi-access network, the router cannot determine the next-hop MAC address for the Ethernet frame without a next-hop address.