If a class B network on the Internet has a subnet mask of 255.255.248.0, what…
2008
If a class B network on the Internet has a subnet mask of 255.255.248.0, what is the maximum number of hosts per subnet?
- A.
1022
- B.
1023
- C.
2046
- D.
2047
Attempted by 355 students.
Show answer & explanation
Correct answer: C
Explanation: step through the mask to find usable hosts per subnet.
Determine the prefix length for the mask 255.255.248.0: the third octet 248 is 11111000, so the mask has 8 + 8 + 5 = 21 ones => /21.
Calculate host bits: 32 - 21 = 11 host bits.
Total addresses per subnet: 2^11 = 2048.
Usable hosts per subnet: subtract 2 reserved addresses (network and broadcast): 2048 - 2 = 2046.
Answer: 2046 usable hosts per subnet.