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Review lab 40 bonus XP

Review the addressing handover

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Objectives

A handover mixes calculations, legacy terminology, and service tests. Its author insists every confident statement can be accepted because the addresses look familiar.

Judge each claim exactly as written. Reject incorrect scope or arithmetic, but do not reject a correct statement just because it uses a special-purpose address.

Verdicts are accept or reject. Every rejection needs one reason code from: private-boundary | mask-mismatch | loopback-scope | link-local-scope.

Handover claims

IPV-1: 172.31.255.255 is inside RFC 1918 private space; that alone does not establish host assignability.
IPV-2: 172.32.0.1 is RFC 1918 private because every 172 address is private.
IPV-3: A /26 mask is 255.255.255.0.
IPV-4: Reaching 127.0.0.1 proves the service is reachable from another host.
IPV-5: 169.254.12.8 is an ordinary routed RFC 1918 address.
IPV-6: With an explicit /26, CIDR uses 26 network bits regardless of the historical class label.

Checks the server runs (3)

  • Every line in the fixture carries a verdict
  • Accept and reject land on the right lines
  • Each rejection cites a valid reason code

Check names are all you see here: the expectations that decide pass or fail, and the reference solution, stay on the server.

Step-by-step hints

The guided walkthrough, in full. It is free: no XP cost, and it does not touch the paid hint ladder or the reveal gate.

  1. Step 1

    Read the request before the artefact

    Read each sentence as a claim with a specific scope. Distinguish address membership from host assignability and remote reachability.

  2. Step 2

    Judge every line, including the boring ones

    Give each fixture line one verdict, retaining its identifier and avoiding duplicates.

    Every line in the fixture carries a verdict

  3. Step 3

    Separate what is wrong from what is merely ugly

    Recalculate the numerical claims and trace where the described traffic can travel. Do not infer that private means trusted.

    Accept and reject land on the right lines

  4. Step 4

    Say why, in the vocabulary the programme uses

    For each rejected claim, select the code for the failed concept rather than a secondary consequence. Accepted claims need no reason.

    Each rejection cites a valid reason code

Rules summary

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  • Paid hints

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  • Reveal solution

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  • Attempt cap

    60 check runs per learner. The runner warns you in the last 10.

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