01-15-2011, 07:34 PM
Here is the full question:
Refer to the exhibit. According to the routing table, where will the router send a packet destined for 10.1.5.65?
Network Interface Next Hop
10.1.1.0 /24 e0 directly connected
10.1.2.0 /24 e1 directly connected
10.1.3.0 /25 s0 directly connected
10.1.4.0 /24 s1 directly connected
10.1.5.0 /24 e0 10.1.1.2
10.1.5.64 /28 e1 10.1.2.2
10.1.5.64 /29 s0 10.1.3.3
10.1.5.64 /27 s1 10.1.4.4
a. 10.1.1.2
b. 10.1.2.2
c. 10.1.3.3 - answer
d. 10.1.4.4
Reason:
When a router needs to forward a packet, it looks at the destination IP address, and then uses the longest matching route in the routing table. The destination IP matches the last four routes but the second last route has a prefix length of /29.
After finding that route, the router will then use the next hop associated with the route selected, i.e. serial 0: 10.1.3.3
Refer to the exhibit. According to the routing table, where will the router send a packet destined for 10.1.5.65?
Network Interface Next Hop
10.1.1.0 /24 e0 directly connected
10.1.2.0 /24 e1 directly connected
10.1.3.0 /25 s0 directly connected
10.1.4.0 /24 s1 directly connected
10.1.5.0 /24 e0 10.1.1.2
10.1.5.64 /28 e1 10.1.2.2
10.1.5.64 /29 s0 10.1.3.3
10.1.5.64 /27 s1 10.1.4.4
a. 10.1.1.2
b. 10.1.2.2
c. 10.1.3.3 - answer
d. 10.1.4.4
Reason:
When a router needs to forward a packet, it looks at the destination IP address, and then uses the longest matching route in the routing table. The destination IP matches the last four routes but the second last route has a prefix length of /29.
After finding that route, the router will then use the next hop associated with the route selected, i.e. serial 0: 10.1.3.3