ICND1 Subnetting 4

Question 1

You need to divide 192.168.50.0/24 into subnets supporting 60 hosts each. Which mask should you use?

Accepted Answer

/26

Answer

A /26 provides 62 usable hosts (64 - 2), which is the smallest mask that supports 60 hosts.

Question 2

What is the network address of the subnet containing 172.16.35.200/20?

Accepted Answer

172.16.32.0

Answer

/20 has a block size of 16 in the third octet; 35 falls in the 32–47 range, so the network is 172.16.32.0.

Question 3

Which of the following addresses is a valid host in the subnet 10.0.0.128/25?

Accepted Answer

10.0.0.200

Answer

The subnet 10.0.0.128/25 covers 10.0.0.128–10.0.0.255; only 10.0.0.200 is a valid host (not the broadcast .255).

Question 4

How many bits must be borrowed from the host portion of a Class B address to create 100 subnets?

Accepted Answer

7

Answer

2^7 = 128 ≥ 100 and 2^6 = 64 < 100, so 7 bits must be borrowed.

Question 5

What is the broadcast address of the subnet 10.20.30.64/27?

Accepted Answer

10.20.30.95

Answer

A /27 has a block size of 32; the subnet starting at .64 ends at .64 + 31 = .95, which is the broadcast.

(ICND1) Interconnecting Cisco Networking Devices Part 1 Practice Test