| Exam 200-301 | Question id=5467 | IP Connectivity |
Examine the partial output of the show ip interface command below.
Router# show ip interface
Senal0 is up, line protocol is up
Internet address is 1.1.1.2/24
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing access list is not set
Inbound access list is not set
GigabitEthernet0/3 is up, line protocol is up
Internet address is 192.162.93.1/28
Broadcast address is 255.255.255.255
Address determined by setup command
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is disabled
Outgoing access list is not set
Inbound access list is not set
What is the subnet broadcast address of the LAN connected to the router from which the command was executed?
| A. |
192.168.93.15 | |
| B. |
192.168.93.255 | |
| C. |
1.1.1.255 | |
| D. |
1.1.1.127 |
In the output we can see there are two interfaces, a serial interface (which goes to another router) and a GigabitEthernet interface (the LAN interface). The LAN interface has an address of 192.168.93.1/28, which is a mask of 255.255.255.240. When this mask is used against the 192.168.93.0 classful network, it yields the following subnets:
192.168.93.0
192.168.93.16
192.168.93.32 192.168.93.48 and so on, incrementing in intervals of 16 in the last octet.
Since the LAN interface has an address of 192.168.93.1, the interface is in the 192.168.93.0/28 network. That networks broadcast address is the last address before the next subnet address of 192.168.93.16. Therefore, the broadcast address of the LAN connected to the router from which the command was executed is 192.168.93.15.
The address 192.168.93.255 is not the broadcast address. If a standard 24-bit mask were used instead of the /28, this would be the broadcast address.
The address 1.1.1.255 is the broadcast address of the network in which the Serial interface resides. The question asked for the LAN interface.
The address 1.1.1.127 would be the broadcast address of the network in which the Serial interface resides if the mask used on the interface were 255.255.255.128. However, that is not the mask, and the question asked for the LAN interface.