Two computers A and B are configured as follows: A has IP address 203.197.2.53…
2024
Two computers A and B are configured as follows: A has IP address 203.197.2.53 and subnet mask 255.255.128.0, B has IP address 203.197.75.201 and subnet mask 255.255.192.0. What one of the following statement is true?
- A.
A and B both assume they are on the same network
- B.
B assumes, A is on same network, A assumes B is on different network
- C.
A assumes, B is on same network, but B assumes, A is on a different network
- D.
A and B both assume they are on different network
Attempted by 176 students.
Show answer & explanation
Correct answer: C
Key idea: each host decides whether the other is on the same subnet by applying its own subnet mask to both IP addresses and comparing the resulting network addresses.
Computer A: IP 203.197.2.53, mask 255.255.128.0 (/17) → network address = 203.197.0.0 (range 203.197.0.0–203.197.127.255).
Computer B: IP 203.197.75.201, mask 255.255.192.0 (/18) → network address = 203.197.64.0 (range 203.197.64.0–203.197.127.255).
Compare from A's perspective: apply A's /17 mask to B's IP → 203.197.0.0, which matches A's network, so A assumes B is on the same network.
Compare from B's perspective: apply B's /18 mask to A's IP → 203.197.0.0, which does not match B's network 203.197.64.0, so B assumes A is on a different network.
Conclusion: A assumes B is on the same network, but B assumes A is on a different network.
A video solution is available for this question — log in and enroll to watch it.