Introduction & architectural analysis Flashcards
(25 cards)
What is a concise textbook definition of software architecture?
The structures of a software system—its elements, the externally visible properties of those elements, and the relationships among them.
Why does software architecture matter to a project?
It communicates design intent among stakeholders, fixes the earliest (and hardest-to-change) decisions, and directly enables or inhibits qualities such as performance and security.
What does IEEE 1471 mean by a stakeholder ‘concern’?
Any interest that affects development, operation, or use of the system—for example performance, reliability, security, evolvability.
In analysis terminology, what is ‘context’?
The developmental, operational, political, and other environmental circumstances that influence the system.
Define an Architecturally Significant Requirement (ASR).
A requirement whose satisfaction has a notable influence on the architecture of the system.
What is the purpose of architectural analysis?
To distil stakeholder concerns and context into a set of architecturally significant requirements (ASRs) that will guide design.
List two core artefacts produced by analysis.
Context diagram and quality-attribute scenarios (QAS).
What key question does a context diagram answer?
Where does our system sit in its wider environment—who/what interacts with it and where are the system boundaries?
Name three kinds of elements typically shown on a context diagram.
System being built, external systems/services, human actors (users or administrators).
What is a quality-attribute scenario (QAS)?
A structured sentence that captures a measurable quality requirement in stimulus–response form.
Give the six standard parts of a full QAS template.
Source, Stimulus, Environment, Artifacts, Response, Response-measure.
Write a short example of a performance QAS.
When 10 000 users (source) submit checkout requests simultaneously (stimulus) under normal load (environment), the payment service (artifact) shall respond with an approval or failure (response) within 500 ms 95 % of the time (response-measure).
What role does an architectural backlog play?
It tracks unresolved design decisions and risks—parallel to but separate from the Scrum product backlog—so architectural work stays visible and iterative.
How do functional requirements differ from quality attributes?
Functional requirements specify what the system must do; quality attributes specify how well it must do it (e.g., speed, availability, security).
What simple, informal drawing is often used to communicate high-level system placement to non-technical stakeholders?
An informal context diagram—boxes for systems/actors, labelled arrows for interactions.
Why are quality attributes considered harder to handle than functionality?
They are harder to measure, have higher variability across domains, and lack exhaustive prior research maturity.
State the main goal of a quality-attribute workshop (QAW).
To elicit, refine, and prioritise quality-attribute scenarios collaboratively with stakeholders.
What is the Rational Unified Process 4 + 1 view model, in one sentence?
A documentation approach that describes a system through logical, process, implementation, and deployment views plus a unifying set of use-case scenarios.
Which three structural views form the ‘3 + 1’ approach used in the course?
Module (development-time), Component & Connector (run-time), Deployment (allocation) views, plus the ASR rationale layer.
How does analysis help resolve conflicting stakeholder concerns?
By translating vague concerns into measurable QASs and prioritising ASRs so trade-offs are explicit before design begins.
What document or artefact captures measurable non-functional requirements during analysis?
Quality-attribute scenarios (QAS) list, often summarised in a utility or prioritisation table.
Explain ‘concerns’ vs. ‘context’ in one line.
Concerns are stakeholder interests; context is the external environment and constraints that frame those interests.
Which analysis artefact is especially useful for explaining the system to executives?
The informal context diagram—no formal notation, easy to grasp at a glance.
Name one scenario-based technique used later to evaluate architectures.
Architecture Trade-off Analysis Method (ATAM) uses scenarios and utility trees to probe quality goals.
