CCNA Network Infrastructure and Connectivity Practice Question
This 200-301 practice question tests your understanding of network infrastructure and connectivity. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. A key principle to apply: subnetting divides an IP address space into smaller blocks by borrowing bits from the host portion to create subnetworks.. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A host is configured as 10.10.20.190/26. Which range contains usable host addresses for that subnet?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
10.10.20.129 to 10.10.20.190
A /26 uses blocks of 64 addresses. In plain language, the ranges are 0–63, 64–127, 128–191, and 192–255. Since the host ends in 190, it belongs to the 128–191 block. In that block, 10.10.20.128 is the network address and 10.10.20.191 is the broadcast address. That leaves 10.10.20.129 through 10.10.20.190 as the usable host range.
This question checks whether you can identify the correct block and then exclude the reserved endpoints properly.
Key principle: Subnetting divides an IP address space into smaller blocks by borrowing bits from the host portion to create subnetworks.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✓
10.10.20.129 to 10.10.20.190
Why this is correct
This is correct because that is the usable host range of the 10.10.20.128/26 subnet.
Related concept
Subnetting divides an IP address space into smaller blocks by borrowing bits from the host portion to create subnetworks.
✗
10.10.20.128 to 10.10.20.191
Why it's wrong here
This is wrong because those include the network and broadcast addresses.
When this WOULD be correct
If the question asked for the range of addresses in the subnet 10.10.20.128/26, then option B would be correct, as it would include all usable addresses from 10.10.20.129 to 10.10.20.190, while still including the network and broadcast addresses.
✗
10.10.20.130 to 10.10.20.191
Why it's wrong here
This is wrong because it excludes one valid host and includes the broadcast address.
When this WOULD be correct
If the question specified a subnet mask of /25 instead of /26, then option C would be correct, as the usable host range would then be 10.10.20.129 to 10.10.20.254, allowing for addresses up to 10.10.20.191.
✗
10.10.20.193 to 10.10.20.254
Why it's wrong here
This is wrong because that range belongs to the next subnet block.
When this WOULD be correct
If the question specified a different subnet, such as 10.10.20.192/26, then option D would be correct, as it would contain usable addresses from 10.10.20.193 to 10.10.20.254 for that subnet.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The 200-301 exam frequently reuses these exact scenarios with slightly different constraints.
✓10.10.20.129 to 10.10.20.190Correct answer▾
Why this is correct
This is correct because that is the usable host range of the 10.10.20.128/26 subnet.
✗10.10.20.128 to 10.10.20.191Wrong answer — click to see why▾
Why this is wrong here
Option B is incorrect because it includes the network address (10.10.20.128) and the broadcast address (10.10.20.191) for the subnet 10.10.20.128/26, which are not usable host addresses.
★ When this WOULD be the correct answer
If the question asked for the range of addresses in the subnet 10.10.20.128/26, then option B would be correct, as it would include all usable addresses from 10.10.20.129 to 10.10.20.190, while still including the network and broadcast addresses.
Why candidates choose this
Candidates may choose this option because it appears to include a broader range of addresses, and they might mistakenly believe it encompasses usable addresses without recognizing the significance of the network and broadcast addresses.
✗10.10.20.130 to 10.10.20.191Wrong answer — click to see why▾
Why this is wrong here
Option C is incorrect because the subnet mask /26 indicates a subnet range of 10.10.20.128 to 10.10.20.191, but the usable host addresses are from 10.10.20.129 to 10.10.20.190, excluding the network and broadcast addresses.
★ When this WOULD be the correct answer
If the question specified a subnet mask of /25 instead of /26, then option C would be correct, as the usable host range would then be 10.10.20.129 to 10.10.20.254, allowing for addresses up to 10.10.20.191.
Why candidates choose this
Candidates may choose this option due to a misunderstanding of subnetting, confusing the usable range with the total range of addresses, or miscalculating the subnet boundaries.
✗10.10.20.193 to 10.10.20.254Wrong answer — click to see why▾
Why this is wrong here
Option D is incorrect because the range 10.10.20.193 to 10.10.20.254 falls outside the subnet defined by 10.10.20.190/26, which only allows for usable addresses from 10.10.20.130 to 10.10.20.190.
★ When this WOULD be the correct answer
If the question specified a different subnet, such as 10.10.20.192/26, then option D would be correct, as it would contain usable addresses from 10.10.20.193 to 10.10.20.254 for that subnet.
Why candidates choose this
Candidates may be tempted by option D because it includes addresses that are numerically close to the given host address, leading to confusion about the correct subnet range.
Analysis generated from the official 200-301blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Common exam traps
Common exam trap: answer the scenario, not the keyword
Be careful not to include the network and broadcast addresses as usable host addresses. Always calculate the subnet boundaries accurately.
Detailed technical explanation
How to think about this question
Subnetting is a fundamental concept in IP networking that allows a single IP network to be divided into multiple smaller networks or subnets. This is done by extending the network mask beyond the default classful mask, borrowing bits from the host portion of the address to create subnet bits. For a /26 subnet mask, which is 255.255.255.192, the network is divided into blocks of 64 IP addresses each. These blocks are contiguous and non-overlapping, allowing efficient address allocation and management.
To determine the usable host range within a /26 subnet, you first identify the network address, which is the first IP in the block, and the broadcast address, which is the last IP in the block. Neither of these addresses can be assigned to hosts. For example, the block 10.10.20.128/26 includes addresses from 10.10.20.128 to 10.10.20.191. Here, 10.10.20.128 is the network address, and 10.10.20.191 is the broadcast address. The usable host addresses are therefore from 10.10.20.129 to 10.10.20.190.
A common exam trap is confusing the network and broadcast addresses with usable hosts, especially when the host IP is near the subnet boundaries. For instance, including 10.10.20.128 or 10.10.20.191 as usable hosts is incorrect and can cause network issues in real Cisco environments. Practically, Cisco routers and switches enforce these rules strictly, so understanding and correctly identifying subnet ranges and usable hosts is essential for configuring interfaces and troubleshooting IP connectivity problems.
KKey Concepts to Remember
Subnetting divides an IP address space into smaller blocks by borrowing bits from the host portion to create subnetworks.
A /26 subnet mask corresponds to 255.255.255.192, which divides an IPv4 Class A, B, or C network into blocks of 64 addresses each.
The first address in a subnet block is the network address and cannot be assigned to hosts.
The last address in a subnet block is the broadcast address and is reserved for network-wide communication.
Usable host addresses are all IPs between the network and broadcast addresses, excluding both.
To find the subnet block for a host, identify the subnet range that contains the host IP based on the subnet mask.
Cisco devices use subnetting rules strictly, so assigning network or broadcast addresses to hosts causes connectivity issues.
Understanding subnet boundaries and usable host ranges is critical for IP address planning 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.
Key takeaway
Subnetting divides an IP address space into smaller blocks by borrowing bits from the host portion to create subnetworks.
Real-world example
How this comes up in practice
A network engineer segments a warehouse floor into three subnets: 20 scanners, 5 printers, and 2 management hosts. Picking the wrong mask wastes addresses or leaves too few usable hosts. Exam questions test whether you can apply CIDR notation, calculate block size, and identify the correct usable-host range for a given prefix.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this 200-301 question in full detail.
Review subnetting divides an IP address space into smaller blocks by borrowing bits from the host portion to create subnetworks., then practise related 200-301 questions on the same topic to reinforce the concept.
Network Infrastructure and Connectivity — This question tests Network Infrastructure and Connectivity — Subnetting divides an IP address space into smaller blocks by borrowing bits from the host portion to create subnetworks..
What is the correct answer to this question?
The correct answer is: 10.10.20.129 to 10.10.20.190 — A /26 uses blocks of 64 addresses. In plain language, the ranges are 0–63, 64–127, 128–191, and 192–255. Since the host ends in 190, it belongs to the 128–191 block. In that block, 10.10.20.128 is the network address and 10.10.20.191 is the broadcast address. That leaves 10.10.20.129 through 10.10.20.190 as the usable host range.
This question checks whether you can identify the correct block and then exclude the reserved endpoints properly.
What should I do if I get this 200-301 question wrong?
Review subnetting divides an IP address space into smaller blocks by borrowing bits from the host portion to create subnetworks., then practise related 200-301 questions on the same topic to reinforce the concept.
What is the key concept behind this question?
Subnetting divides an IP address space into smaller blocks by borrowing bits from the host portion to create subnetworks.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This 200-301 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 200-301 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.