IPv4 subnetting worksheet with answers

Free printable IPv4 subnetting worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

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Name: ____________________ Date: ____________

1.Easy

A subnet has the mask 255.255.255.224. What is its prefix length p?

255.255.255.224

p =

2.Easy

How many usable host addresses H are there in an IPv4 subnet with prefix /21?

/21

H =

3.Medium

A subnet uses the mask 255.255.255.248. How many usable host addresses H does it have?

255.255.255.248

H =

4.Medium

The network 192.168.35.0/24 is divided into /29 subnets, numbered 1, 2, 3, … from the lowest address (subnet 1 starts at .0). What is the fourth octet x of the network address of subnet 6?

192.168.35.0/24/29subnet 6 (subnet 1 starts at .0)

x =

5.Hard

A router has routes to these networks: 10.86.163.0/24, 10.86.164.0/24, 10.86.165.0/24, 10.86.166.0/24, 10.86.167.0/24, 10.86.168.0/24. What is the longest prefix length p of a single summary route that covers all of them?

10.86.163.0/24 … 10.86.168.0/24

p =

6.Hard

The network 192.168.0.0/24 is split with VLSM for these LANs: A: 5 hosts, B: 19 hosts, C: 22 hosts, D: 121 hosts. Subnets are allocated from .0 upwards, the LAN with the most hosts first, each with the smallest subnet that fits. What is the fourth octet x of the network address of LAN B?

A: 5B: 19C: 22D: 121

x =

Answer key

1. p = 27
2. H = 2046
3. H = 6
4. x = 40
5. p = 20
6. x = 160

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