Chapter 30 — Verification laboratory I

Chapter 30 — Verification laboratory I

Lesson map

Lesson 30 published. Map, example, EX088.

flowchart TD
  N0["Learning outcomes"]
  N1["30.1 Planning verification"]
  N2["30.2 Evidence"]
  N3["30.3 Findings"]
  N4["Synthesis"]
  N0 --> N1 --> N2 --> N3 --> N4
  N4 --> EX["Worked example"]
  EX --> Q["Exercise EX088"]

Logical drawing

flowchart LR
  N0["Learning outcomes"]
  N1["30.1 Planning verification"]
  N2["30.2 Evidence"]
  N3["30.3 Findings"]
  N4["Synthesis"]
  N0 --> N1 --> N2 --> N3 --> N4 --> Q["EX088"]

[Learning outcomes]
    |
    v
[30.1 Planning verification]
    |
    v
[30.2 Evidence]
    |
    v
[30.3 Findings]
    |
    v
[Synthesis]
    |
    v
[Worked example] --> [Exercise EX088]

Learning outcomes

You will (1) verify that controls operate as described; (2) collect and record evidence properly; (3) report verification findings.

30.1 Planning verification

In the verification laboratory, Nadia tests the vendor access broker against its control descriptions. For each control she writes a test step, the expected result and the evidence to keep. She checks that a vendor without multi-factor authentication cannot sign in, that a session without approval cannot start, that sessions end after four hours and that recordings appear in the archive. She uses a test vendor account in a laboratory copy of the broker, so production is not disturbed. Each expected result is written before the test runs, so a pass cannot be decided after seeing the outcome.

30.2 Evidence

For each test Nadia records the date, the tester, the steps, the result and supporting artefacts such as screenshots and log extracts. She names files consistently and stores them where they cannot be edited after filing. She learns that evidence must allow another person to understand and repeat the test. An auditor will not accept a statement that a test passed without seeing what was done and what was observed, and a future engineer will need the same detail. Prof. Brenner asks whether a screenshot alone would do, and Nadia adds log extracts because a screenshot cannot show what happened before or after it.

30.3 Findings

Most tests pass, but one fails: a session approved for one device can reach a second device on the same network segment. Nadia records the finding with its severity, the evidence and a recommended fix: restricting the jump host's routes per session. She reports it to the implementation team, who fix it and ask her to retest. The retest passes and is recorded. She learns that verification is valuable precisely because it finds what designers assumed would not happen. Restricting jump host routes per session closes the second-device path without slowing approved work.

Worked example

Nadia verifies four broker controls in a lab copy, records repeatable evidence and finds and retests a route restriction failure.

Synthetic case. The broker and tests are synthetic.

Errors and limits

Lab copies differ from production. Tests cover planned cases only.

Exercises

• EX088 — Lab copy. Why test in a laboratory copy? Rubric: 3 = so production is not disturbed;; 2 = safety;; 1 = vague;; 0 = none.
• EX089 — Evidence fields. What does Nadia record for each test? Rubric: 3 = date, tester, steps, result and artefacts;; 2 = evidence;; 1 = vague;; 0 = none.
• EX090 — Failed test. Which test failed? Rubric: 3 = an approved session could reach a second device;; 2 = routing;; 1 = vague;; 0 = none.

Synthesis

Verification with repeatable evidence finds failures that designers assumed away.

Continue studying — chapter 30 of 50

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