Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
An interface is configured with 10.24.7.158/27. What is the broadcast address of that subnet?
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
Best answer
10.24.7.159
Correct. It is the last address in the /27 block.
B
Distractor review
10.24.7.191
That is the end of the next larger /26 range, not this /27 block.
C
Distractor review
10.24.7.127
That is the end of the previous /27 block.
D
Distractor review
10.24.7.160
That is the network address of the next /27 block.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is mistaking the broadcast address for the network address of the next subnet or the last address of a different subnet block. For example, 10.24.7.160 is the network address of the next /27 subnet, not the broadcast address of the current subnet. Candidates often confuse the last usable host address with the broadcast address or select an address from an adjacent subnet block. This mistake leads to incorrect subnetting answers and can cause interface misconfigurations in real networks, resulting in communication failures.
Technical deep dive
How to think about this question
Subnetting is a fundamental concept in IP networking that breaks a larger network into smaller, manageable segments called subnets. Each subnet has a unique network address, a range of usable host addresses, and a broadcast address. The subnet mask determines the size of each subnet. For a /27 mask, which is 255.255.255.224, the subnet contains 32 IP addresses (2^5), including the network and broadcast addresses. This subnetting allows efficient use of IP addresses and better network organization. To determine the broadcast address for an IP configured with 10.24.7.158/27, first identify the subnet range. Since /27 means blocks of 32 addresses, the subnet ranges start at multiples of 32 in the last octet: 0, 32, 64, 96, 128, 160, etc. The IP 10.24.7.158 falls within the 10.24.7.128 to 10.24.7.159 block. The broadcast address is the highest address in this block, which is 10.24.7.159. This address is reserved for broadcasting to all hosts in the subnet. A common exam trap is confusing the broadcast address with the network address of the next subnet or the last address of a different subnet block. For example, 10.24.7.160 is the network address of the next /27 subnet, not the broadcast of the current one. Cisco routers and switches rely on correct subnetting to forward traffic properly, so misidentifying broadcast addresses can lead to routing errors or failed communications. Understanding subnet boundaries and broadcast address calculation is critical for CCNA success and practical network design.
KKey Concepts to Remember
- Subnetting divides an IP network into smaller address blocks, each with a defined network, broadcast, and host range based on the subnet mask.
- A /27 subnet mask corresponds to 255.255.255.224, which creates subnets with 32 IP addresses each, including network and broadcast addresses.
- The broadcast address is always the last IP address in the subnet range and is used to send packets to all hosts within that subnet.
- To find the broadcast address, identify the subnet block containing the IP and calculate the highest address in that block.
- Cisco devices use the broadcast address to forward broadcast traffic within a subnet, which is critical for protocols like ARP and DHCP.
- Incorrectly identifying the broadcast address can cause communication failures or misconfigured interfaces in Cisco networks.
- Subnetting knowledge is essential for IP address planning, routing decisions, and efficient network segmentation in Cisco environments.
- Understanding subnet boundaries helps avoid overlapping IP ranges and ensures proper packet delivery and network isolation.
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.
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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?
Subnetting divides an IP network into smaller address blocks, each with a defined network, broadcast, and host range based on the subnet mask.
What is the correct answer to this question?
The correct answer is: 10.24.7.159 — A /27 uses blocks of 32 addresses. The block containing .158 is 10.24.7.128 through 10.24.7.159, so .159 is the broadcast address.
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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