For the subnet mask 255.255.31.0, which of the following pairs of IP addresses…
2024
For the subnet mask 255.255.31.0, which of the following pairs of IP addresses can produce the same network number after bitwise AND with the mask?
- A.
172.57.88.62 and 172.56.87.23
- B.
10.35.28.2 and 10.35.29.4
- C.
191.203.31.87 and 191.234.31.88
- D.
128.8.129.43 and 128.8.161.55
Attempted by 59 students.
Show answer & explanation
Correct answer: D
To check whether two IP addresses could belong to this network, apply the given mask using bitwise AND and compare the resulting network numbers.
For option D:
128.8.129.43 & 255.255.31.0 = 128.8.1.0 (129 = 10000001₂)
128.8.161.55 & 255.255.31.0 = 128.8.1.0 (161 = 10100001₂)
Both addresses give the same network number, 128.8.1.0. Therefore, option D is correct.