CPSA Quality Attributes and Scenarios Questions and Answers

Question 1

An architect is defining a quality scenario for system availability. The scenario reads: 'Under normal operation, an unexpected database connection failure occurs.' Which essential component of a quality scenario is missing from this statement?

Accepted Answer

Response and Response Measure

Answer

A complete quality scenario consists of six parts: source, stimulus, artifact, environment, response, and response measure. The provided statement includes the environment ('Under normal operation') and the stimulus ('an unexpected database connection failure occurs'). However, it fails to specify how the system should react (the response) and the measurable criteria for success (the response measure), such as 'the system logs the error and restores the connection within 5 seconds'.

Question 2

A stakeholder states that a new online retail system must be 'user-friendly'. To transform this statement into a testable quality requirement, the architect decides to create a quality scenario. Which of the following is the BEST example of a 'Response Measure' for a usability scenario?

Accepted Answer

A new user can complete a purchase in under 90 seconds.

Answer

A response measure must be a quantifiable and testable metric that defines the success of the response. 'A new user can complete a purchase in under 90 seconds' provides a specific, measurable target (less than 90 seconds) that can be objectively tested. The other options describe a desired qualitative outcome, a stimulus, or the environment, but not a concrete measure.

Question 3

Which of the following describes the primary purpose of using a 'general scenario' when defining quality attributes?

Accepted Answer

To provide a system-independent template or checklist to help elicit and specify concrete quality requirements.

Answer

General scenarios are system-independent templates that describe a common type of stimulus and response for a particular quality attribute (like modifiability or security). They serve as a starting point or a checklist to guide architects and stakeholders in creating specific, context-relevant quality scenarios for their particular system. They are not the final detailed requirement themselves but a tool to create them.

Question 4

A software architect is using a utility tree to prioritize quality requirements. A specific scenario is evaluated as having (High Business Value, Low Architectural Impact). How should the architect typically interpret this scenario?

Accepted Answer

This is a 'quick win' that delivers significant value to stakeholders and should be prioritized, as it is relatively easy to achieve.

Answer

In a utility tree, scenarios are often ranked by business value and architectural impact (or difficulty). A scenario with high business value but low architectural impact represents a requirement that is very important to stakeholders but relatively straightforward to implement from an architectural standpoint. These are ideal candidates to prioritize as they provide maximum value for a comparatively low level of effort or risk.

Question 5

A team is developing a system for processing financial transactions. A key quality attribute is security. Which scenario best represents a concrete, testable security requirement?

Accepted Answer

An external actor with no credentials attempts to access a customer's transaction history via a public API endpoint; the system rejects the request and logs the attempt within 100ms.

Answer

This is the only option structured as a complete quality scenario. It specifies the source (external actor), stimulus (attempts to access data), artifact (public API endpoint), response (rejects and logs), and response measure (within 100ms). The other options are vague goals or general statements that lack the specific, measurable, and testable components of a well-defined scenario.

CPSA Exam Practice Test

CPSA Exam Practice Test

CPSA Quality Attributes and Scenarios Questions and Answers