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A requirement is (1) a condition or capability a user needs to solve a problem, (2) a condition or capability a system must possess to satisfy a contract or standard, or (3) a documented representation of (1) or (2). The three-part definition is deliberately layered, because the...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026

You can choose the instrument (natural language → structured models → interaction models → formal model), the structure, the precision, and the depth (deepness) of the representation. * Four dials you set independently; turning any of them up costs more effort, so each is scaled...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026

A functional requirement says what the system does — a result or behaviour a function must provide; a quality requirement says how well it does it (performance, availability, security…) and is defined as everything not covered by the functional ones. This is the most fundamental...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026

Elicit the stakeholders' requirements, document them suitably, validate and verify them, and manage them — and you do all four across the entire life cycle of the system, not just once at the start. * Management is drawn as the band around the other three, not as a fourth step i...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026

The system boundary draws the line between the system and its environment; the context boundary draws a second, outer line between the environment that matters and the environment you can ignore. * The system boundary separates the system from its environment; the context bounda...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026

The goal is to know the relevant requirements, reach a consensus among stakeholders about them, document them to standards, and manage them systematically — all to minimise the risk of delivering a system that does not meet the stakeholders' real needs. Requirements engineering i...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026

Don't ask "is the spec complete?" — ask "how much must we invest to shrink the risk to a size we can accept?" Completeness is never the goal; managed risk is. * The stopping point is set by the risk this project can accept — the same curve, two different answers. * The naive fra...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026

Three modelling views — a system component diagram (components + interfaces), a use case diagram (actors + functions) and a business object model (business objects + relationships) — plus screen flows, the screens themselves and the outputs, with anything left over listed and ref...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026

A requirement specification is a systematically organised collection of requirements for a system or component that satisfies given criteria; non-functional requirements are the "how well" qualities — performance, scalability, portability, usability, compatibility, localization,...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026

Sources: stakeholders, documents, and existing systems. Types: functional (e.g. "login"), quality / non-functional (e.g. "secure storage of log data"), and general conditions or regulations (e.g. "must be live by summer", "PCI-DSS compliant"). * Any source can yield any of the t...

Quiz: SPRG / Security Requirements Fundamentals | updated: Aug 27, 2026