Sizing the IPv4 Plan: /23 Server Room, No Overlap

Create structured addressing plans for IPv4 and IPv6

Answer Correct answer: B — A /23 (512 addresses) fits the 500-host server room; the plan also sizes the remote (/25) and access (/27) sites without overlap, maximizing usable subnets.

Refer to the exhibit. An architect is designing an IPv4 plan using the 172.16.0.0/16. The design must maximize the number of subnets while meeting these requirements: • 500 hosts within the server room • 100 hosts at the remote site • 25 hosts at the access site Which plan must the architect choose? -

Server room 172.16.8.0/21
Server room 172.16.2.0/23 Correct Answer
Server room 172.16.2.0/23
Server room 172.16.4.0/22

Community Votes

100%

100% of anonymous learners picked answer B. Votes are pick records left by other test-takers — they are not the verified answer.

Community Insight

Pick the smallest prefix that holds the host count: 500 to /23, 100 to /25, 25 to /27. Then verify no overlap. B is the only option that satisfies all three without overlap.

For 172.16.0.0/16, the 500-host server room needs a /23 (512 addresses), the 100-host remote site a /25 (128), and the 25-host access site a /27 (32). Option B allocates these without overlap, meeting capacity while maximizing the number of available subnets.

Picking A (server /21) or D (server /22): those waste addresses and/or overlap the remote/access sites; C under-sizes the remote site (not enough hosts for 100). Only B fits all and stays contiguous.

Community Discussion (4 comments)

935608e 👍 2 Selected: B

B is the only one that makes sense -> 23 -> 512, 25 ->128 and 27 ->32

PicoOstrava 👍 3 Selected: B

Option B: Server room: 172.16.2.0/23 (provides 512 IPs — good for 500 hosts). Remote site: 172.16.4.128/25 (provides 128 IPs — good for 100 hosts). Access site: 172.16.5.32/27 (provides 32 IPs — good for 25 hosts). This option meets all the requirements and is very efficient in terms of IP address allocation

muffedtrims 👍 2 Selected: B

A-incorrect, remote and access overlap B-correct, maximizes subnets available without overlap and provides each site enough hosts C-incorrect, not enough hosts at remote site D-incorrect, remote and access sites overlap

Swiz005 👍 3

How about B?

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Expert Analysis

Why the Answer Is Correct

B is correct. The server room needs 500 hosts, so a /23 (512 addresses) is the right size; B also sizes the remote site (100 hosts) and access site (25 hosts) without overlapping, maximizing usable subnets within 172.16.0.0/16.

Why the Other Options Are Wrong

A (/21 server) and D (/22 server) waste addresses and overlap the remote/access allocations. C uses a /23 for the server but under-sizes the remote site, leaving it unable to hold 100 hosts. Only B meets every requirement.

Community Comment Notes

The vote is B (100). Commenters confirm /23 gives 512 for the server room, /25 for the remote site, and /27 for the access site, with no overlap.

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