Class C Subnet Masks

Question 1

255.255.255.0

Answer 1

Class C default network mask
24 network bits, 8 host bits (no borrowed bits)

1 network, 254 hosts

Question 2

255.255.255.128

Answer 2

25 network bits (1 borrowed), 7 host bits

2 subnets, 126 hosts per subnet

Question 3

255.255.255.192

Class C

Answer 3

26 network bits (2 borrowed), 6 host bits

4 subnets, 62 hosts per subnet

Question 4

255.255.255.224

Class C

Answer 4

27 network bits (3 borrowed), 5 host bits

8 subnets, 30 hosts per subnet

Question 5

255.255.255.240

Class C

Answer 5

28 network bits (4 borrowed), 4 host bits

16 subnets, 14 hosts per subnet

Question 6

255.255.255.248

Class C

Answer 6

29 network bits (5 borrowed), 3 host bits

32 subnets, 6 hosts per subnet

Question 7

255.255.255.252

Class C

Answer 7

30 network bits (6 borrowed), 2 host bits

64 subnets, 2 hosts per subnet

Question 8

255.255.255.254

Class C

Answer 8

31 network bits (7 borrowed), 1 host bit

128 subnets, 2 IP addresses; this is described in RFC 3021 as a point-to-point link. Both IP addresses are used as hosts, and broadcasts are limited.