100-150 Question 90
Single answerA network administrator is tasked with configuring a new subnet for a small office. The administrator is given the IP address range 192.168.10.0/24 and decides to divide it into four smaller subnets. Which of the following prefixes would correctly represent one of the new subnets?
- A
192.168.10.0/25
- B
192.168.10.0/26
- C
192.168.10.0/27
- D
192.168.10.0/28
Show answer and explanation
Correct answer: B
Explanation
To divide a /24 network into four equal subnets, the prefix length must increase by 2 bits (from /24 to /26). Each subnet in a /26 network would have 64 total addresses (62 usable for hosts after reserving two for network and broadcast addresses). This matches the administrator's requirement for four subnets in this scenario.
- A. Incorrect.
192.168.10.0/25 divides the original /24 network into two subnets, not four. Each subnet would have 128 available addresses, which does not match the requirement for four subnets.
- B. Correct.
192.168.10.0/26 divides the original /24 network into four equal subnets. Each subnet would have 64 available addresses, which satisfies the requirement for four subnets.
- C. Incorrect.
192.168.10.0/27 divides the original /24 network into eight subnets, which exceeds the requirement for four subnets. Each subnet would have 32 available addresses, which is unnecessarily small for this scenario.
- D. Incorrect.
192.168.10.0/28 divides the original /24 network into sixteen subnets, which far exceeds the requirement for four subnets. Each subnet would have only 16 available addresses, which is too small for most practical uses in this case.