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optional · CSS study notes

Requirements Sign-off (2017)

CSS CS Optional — Paper-I, Section-B, Topic V.

🔑 Definition

  • Formal end-of-RE step: customer/stakeholders review, agree to, and approve the SRS.
  • Marks it as officially agreed baseline for rest of project.

📌 Why It Matters

  • Enforces "Validation" — without it, no agreed reference point for "did we build the right product."

📌 What It Protects Against

  • Scope creep
  • Disputes over what was agreed
  • Wasted rework

📌 Typical Elements

  • Reviewed, version-numbered SRS
  • Documented stakeholder approval
  • Defined change-control process for post-sign-off changes

📌 Where It Sits

  • After validation confirms requirements meet needs
  • Before design begins

⚠️ MCQ Trap

  • Sign-off happens after validation, before design — placing it earlier or treating it as ongoing (not a formal milestone) is a common error.

📜 Past-Paper Questions & MCQs (CSS 2016–2026)

2017 · Paper-I · Q4(c) · 6 marks

Q. Discuss the importance of requirements engineering in the success of a software project. Explain in detail the process of 'Requirements Sign-off'.

Ans.

  • Importance: requirements errors are the most costly to fix late, and most project failures come from unclear, missing or changing requirements. Good requirements engineering defines the right product, reduces rework, gives a basis for estimating, testing and contracts, and aligns users and developers.
  • Requirements sign-off is the formal approval by the customer (and key stakeholders) that the documented requirements are complete, correct and agreed.
  • Process:
    • finalise the SRS after elicitation, analysis and validation
    • review the SRS with all stakeholders (walkthrough or inspection) and resolve comments
    • check that requirements are clear, consistent, testable and prioritised
    • obtain written approval (signatures) from the customer and project manager
    • baseline the document under change control
  • After sign-off: changes follow a formal change-request process.

2022 · Paper-I · Q7(c) · 6 marks

Q. Write one user requirement and one system requirement for "Automatically highlight incorrect spelling mistakes in an MS Word document".

Ans.

  • User requirement (high-level, natural language, for the customer): "The word processor shall automatically mark misspelled words while the user types, so that the user can see and correct them."
  • System requirement (detailed, for developers): "The system shall compare each completed word against the selected-language dictionary and underline unrecognised words with a red wavy line within one second. Right-clicking a marked word shall display up to five suggested corrections and an Ignore option."

2026 · Paper-I · Q8(b) · 6 marks

Q. The client wants "very strong security" while teachers want "fast login without multiple checks". Explain how the team should resolve this conflict using proper software engineering techniques, and the impact of wrong requirement handling on the SDLC.

Ans.

  • Resolve the conflict:
    • Elicit and analyse with both groups. Identify the real needs behind the words (protect exam data versus save teachers' time).
    • Make them measurable: for example login within 3 seconds, and two-factor authentication only for sensitive actions such as grading.
    • Negotiate and prioritise (MoSCoW or voting) and find a compromise: single sign-on, "remember this device", risk-based authentication.
    • Prototype the login flow and get feedback, record the decision in the SRS and obtain sign-off.
    • Manage with change control and traceability.
  • Impact of wrong handling on the SDLC: the wrong design is built, rework is costly in later phases, schedule and budget overruns follow, testing cannot verify vague requirements, users reject the product, and maintenance cost rises.

2018 · Related

  • 2018 Q7(a) verification vs validation: see Difference between Software Validation and Verification (2017).