An organization is granted the block 130.56.0.0/16. The administrator wants to…
2022
An organization is granted the block 130.56.0.0/16. The administrator wants to create 1024 subnets. .
Find first and last addresses of last subnet.
- A.
130.56.0.0 130.56.254.255
- B.
130.56.255.0 130.56.255.255
- C.
130.56.0.192 130.255.255.255
- D.
130.56.255.192 130.56.255.255
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Correct answer: D
Final answer: 130.56.255.192 to 130.56.255.255
Start with the given block: 130.56.0.0/16. You need 1024 subnets.
Since 1024 = 2^10, you must borrow 10 bits from the host portion.
New prefix length = 16 + 10 = /26.
Addresses per subnet = 2^(32 - 26) = 64 addresses (62 usable hosts).
Subnets increment by 64 in the last octet. The last subnet index is 1023, so offset = 1023 × 64 = 65472, which corresponds to .255.192 in the last two octets.
Therefore the last subnet's network address = 130.56.255.192 and its broadcast (last address) = 130.56.255.255.
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