Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
A host is configured with 10.10.10.33/27. What is the broadcast address of its 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
Distractor review
10.10.10.31
This is wrong because .31 is the broadcast of the previous /27 block.
B
Best answer
10.10.10.63
This is correct because .33 is in the 32–63 subnet.
C
Distractor review
10.10.10.32
This is wrong because .32 is the network address of the block.
D
Distractor review
10.10.10.64
This is wrong because .64 is the start of the next subnet.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is mistaking the network address or the broadcast address of an adjacent subnet for the correct broadcast address. Candidates often select 10.10.10.31 or 10.10.10.32 because they are close numerically to 10.10.10.33, but these addresses belong to the previous or current subnet’s network address, respectively. The trap exploits confusion about subnet boundaries and the increment size of /27 subnets, which is 32 addresses. Misidentifying the subnet block leads to choosing an incorrect broadcast address, which can cause routing and communication failures in real networks.
Technical deep dive
How to think about this question
Subnetting is a fundamental concept in IP networking that divides a larger network into smaller, manageable sub-networks or subnets. A /27 subnet mask means that the first 27 bits of the IP address are used for the network portion, leaving 5 bits for host addresses. This results in 32 IP addresses per subnet, including network and broadcast addresses. The subnet mask for /27 is 255.255.255.224, which defines the block size and address range for each subnet. To determine the broadcast address of a subnet, you first identify the subnet block in which the host IP resides. For a /27 subnet, address blocks increment by 32 (e.g., 0–31, 32–63, 64–95). The broadcast address is always the highest address in the subnet block. Since 10.10.10.33 falls within the 32–63 range, the broadcast address is 10.10.10.63. This address is reserved for broadcasting to all hosts within that subnet. A common exam trap is confusing the network address, broadcast address, and usable host addresses within a subnet. For example, 10.10.10.32 is the network address of the subnet containing 10.10.10.33, not the broadcast. Similarly, 10.10.10.31 is the broadcast of the previous subnet block (0–31), not the current one. Understanding these boundaries is critical for subnetting questions on the CCNA exam and for practical network design and troubleshooting.
KKey Concepts to Remember
- A /27 subnet mask divides an IP network into blocks of 32 addresses, including network and broadcast addresses.
- The broadcast address is the highest IP address in a subnet block and is used to send packets to all hosts within that subnet.
- To find a subnet’s broadcast address, identify the subnet block containing the host IP and select the last address in that block.
- The network address is the first address in the subnet block and cannot be assigned to hosts.
- Subnet boundaries increment by the block size determined by the subnet mask, such as 32 for a /27 mask.
- Incorrectly selecting an address from an adjacent subnet block as the broadcast address is a common subnetting mistake.
- Cisco devices use subnet masks to determine network and broadcast addresses for routing and packet forwarding decisions.
- Understanding subnet increments and address roles is essential for configuring IP addressing and troubleshooting in Cisco networks.
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
Related 200-301 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
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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 blocks of 32 addresses, including network and broadcast addresses.
What is the correct answer to this question?
The correct answer is: 10.10.10.63 — A /27 uses address blocks of 32. In practical terms, the ranges are 0–31, 32–63, 64–95, and so on. Because .33 falls inside the 32–63 block, the broadcast address is the last address in that block, which is 10.10.10.63. This is a classic subnet-boundary question. The trick is to identify the correct block first and then choose its last address as the broadcast.
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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