Subnetting Practice Questions with Solved Answers

 

Subnetting Practice Questions with Solved Answers

Question 1

Find the network address and broadcast address of:
192.168.1.10 /24

Solution

• /24 means subnet mask = 255.255.255.0

• Network address → 192.168.1.0

• Broadcast address → 192.168.1.255

✅ Answer:
Network: 192.168.1.0
Broadcast: 192.168.1.255

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Question 2

How many hosts are available in a /26 network?

Solution

• Total bits = 32

• Host bits = 32 − 26 = 6

• Hosts = $2^6 − 2 = 62$

✅ Answer: 62 usable hosts

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Question 3

What is the subnet mask of /27?

Solution

• /27 means 27 network bits

• Subnet mask = 255.255.255.224

✅ Answer: 255.255.255.224

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Question 4

Find the subnet size (block size) of a /28 network.

Solution

• Last octet mask = 240

• Block size = 256 − 240 = 16

✅ Answer: 16 IP addresses per subnet

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Question 5

How many subnets are created if you borrow 3 bits?

Solution

• Number of subnets = $2^3 = 8$

✅ Answer: 8 subnets

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Question 6

Identify the subnet of IP address:
10.0.0.77 /25

Solution

• /25 subnet mask = 255.255.255.128

• Block size = 128

• Subnets:

  • 10.0.0.0 – 10.0.0.127

  • 10.0.0.128 – 10.0.0.255

• IP 10.0.0.77 falls in first subnet

✅ Answer: 10.0.0.0 /25

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Question 7

What is the broadcast address of:
172.16.5.33 /30

Solution

• /30 mask = 255.255.255.252

• Block size = 4

• Nearest network = 172.16.5.32

• Broadcast = 172.16.5.35

✅ Answer: 172.16.5.35

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Question 8

How many usable hosts are in a /30 subnet and where is it used?

Solution

• Host bits = 2

• Usable hosts = $2^2 − 2 = 2$

• Commonly used for point-to-point links

✅ Answer:
2 usable hosts, used for router-to-router links