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.

New worksheet Practise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________ Date: ____________

1.Easy

An access list must match the network 192.168.1.0/25. Access lists use a wildcard mask, the inverse of the subnet mask. What is the fourth octet x of the wildcard mask?

/25

x =

2.Easy

How many usable host addresses H are there in an IPv4 subnet with prefix /23?

/23

H =

3.Medium

The network 192.168.10.0/24 must be divided into at least 16 equal subnets. If you borrow as few bits as possible, how many usable hosts H does each subnet have?

192.168.10.0/2416 subnets

H =

4.Medium

A subnet uses the mask 255.255.255.240. How many usable host addresses H does it have?

255.255.255.240

H =

5.Hard

A router has routes to these networks: 10.119.155.0/24, 10.119.156.0/24, 10.119.157.0/24, 10.119.158.0/24. What is the longest prefix length p of a single summary route that covers all of them?

10.119.155.0/24 … 10.119.158.0/24

p =

6.Hard

The network 192.168.245.0/24 is split with VLSM for these LANs: A: 54 hosts, B: 37 hosts, C: 7 hosts, D: 16 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 C?

A: 54B: 37C: 7D: 16

x =

Answer key

1. x = 127
2. H = 510
3. H = 14
4. H = 14
5. p = 21
6. x = 160

Full step-by-step solutions: practise this topic on examproblems.com.