Subnetting Practice Questions with Solved Answers

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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

Question 2

How many hosts are available in a /26 network?

Solution

  • Total bits = 32

  • Host bits = 32 − 26 = 6

  • Hosts = 26−2=622^6 − 2 = 62

✅ Answer: 62 usable hosts

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

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

Question 5

How many subnets are created if you borrow 3 bits?

Solution

  • Number of subnets = 23=82^3 = 8

✅ Answer: 8 subnets

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

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

Question 8

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

Solution

  • Host bits = 2

  • Usable hosts = 22−2=22^2 − 2 = 2

  • Commonly used for point-to-point links

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

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