Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
Exhibit
Host IP: 192.168.14.77/27
Exhibit: A host has address 192.168.14.77/27. Which address is its valid default gateway if the first usable address in the subnet is chosen for the router interface?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Distractor review
192.168.14.63
That is the broadcast address of the previous subnet.
B
Distractor review
192.168.14.64
That is the network address of this subnet.
C
Best answer
192.168.14.65
That is the first usable address in 192.168.14.64/27.
D
Distractor review
192.168.14.95
That is the broadcast address of this subnet.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A common exam trap is mistaking the network or broadcast address for a valid default gateway. For example, 192.168.14.64 is the network address for the 192.168.14.64/27 subnet and cannot be assigned to any device. Similarly, 192.168.14.95 is the broadcast address and is reserved for broadcast traffic. Selecting either as the default gateway will cause routing and communication failures. Candidates often overlook the subnetting rules and assume the first or last address in the range is usable, which is incorrect. Understanding the distinction between network, broadcast, and usable host addresses is essential to avoid this mistake.
Technical deep dive
How to think about this question
Subnetting divides an IP network into smaller segments called subnets, each with a unique network address and range of usable host addresses. A /27 subnet mask means 27 bits are fixed for the network portion, leaving 5 bits for host addresses, resulting in 32 IP addresses per subnet. These 32 addresses include one network address, one broadcast address, and 30 usable host addresses. The network address identifies the subnet itself, while the broadcast address is used to send packets to all hosts within that subnet. To determine the valid default gateway for a host, you first identify the subnet the host belongs to by applying the subnet mask to its IP address. For 192.168.14.77/27, the subnet range is 192.168.14.64 to 192.168.14.95. The first usable host address in this range is 192.168.14.65, which is typically assigned to the router interface acting as the default gateway. This address allows the host to send traffic outside its subnet. A common exam trap is confusing network, broadcast, and usable host addresses. For example, 192.168.14.64 is the network address and cannot be assigned to a host or gateway. Similarly, 192.168.14.95 is the broadcast address and is reserved for broadcast traffic. Selecting these addresses as gateways leads to network communication failures. Understanding these distinctions is critical for correctly configuring routing and gateway addresses in Cisco networks.
KKey Concepts to Remember
- A /27 subnet mask divides an IP network into subnets with 32 total addresses, including network, broadcast, and usable host addresses.
- The network address is the first address in the subnet and cannot be assigned to hosts or routers.
- The broadcast address is the last address in the subnet and is reserved for sending packets to all hosts in that subnet.
- The first usable host address in a subnet is typically assigned to the router interface acting as the default gateway.
- Hosts use the default gateway address to send traffic destined for outside their local subnet.
- Subnetting requires calculating the subnet range by applying the subnet mask to the host IP address.
- Choosing the network or broadcast address as a default gateway causes communication failures.
- Cisco devices rely on correct subnetting and gateway configuration to route traffic properly between subnets.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Related practice questions
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A router learns the same prefix from both OSPF and EIGRP. Which route is installed by default?
Question 2
A router shows this output: R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.1.1.2 1 FULL/DR 00:00:34 192.168.12.2 GigabitEthernet0/0 10.1.1.3 1 2WAY/DROTHER 00:00:39 192.168.12.3 GigabitEthernet0/0 Which statement is correct?
Question 3
What is the OSPF metric called?
Question 4
A non-root switch has two uplinks toward the root bridge. One path has a lower total STP cost than the other. What role will the lower-cost uplink have?
Question 5
A router interface applies this ACL inbound: 10 deny tcp any any eq 80 20 permit ip any any A user reports that web browsing to a server by IP address fails, but ping works. Which statement best explains the behavior?
Question 6
A router learns route 198.51.100.0/24 from OSPF with AD 110 and also has a static route to the same prefix configured with AD 150. Which route is installed?
FAQ
Questions learners often ask
What does this 200-301 question test?
A /27 subnet mask divides an IP network into subnets with 32 total addresses, including network, broadcast, and usable host addresses.
What is the correct answer to this question?
The correct answer is: 192.168.14.65 — A /27 has a block size of 32. Address 192.168.14.77 falls in the 192.168.14.64/27 subnet, where the usable host range is 192.168.14.65 through 192.168.14.94. The first usable address is 192.168.14.65.
What should I do if I get this 200-301 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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