Use Cases - USP Flashcards
What are non-functional requirements (NFRs)?
System qualities describing how well a system performs its functions, e.g., usability, performance, and security.
How are NFRs related to functional requirements?
NFRs describe the system’s design qualities, while functional requirements describe what the system does for users.
How are NFRs modeled?
By attaching them as comments to relevant functional requirements.
What is usability in software design?
Design focused on helping users complete tasks with minimal cognitive effort, improving effectiveness, efficiency, and satisfaction.
What are the three parts of usability?
Effectiveness: Users find what they want; Efficiency: Minimal resources/effort; Satisfaction: Users enjoy the experience.
What is performance in software?
A measure of latency and reliability, ensuring the system is fast enough to match or exceed users’ cognitive processing speeds.
What are key considerations for performance?
Volume of data, processing at each end, bandwidth, bottlenecks, and interdependencies in hardware/software.
What is the relationship between usability and performance?
Better performance increases usability, provided the system doesn’t slow down user tasks.
What is security in software?
Protecting sensitive data, system integrity, and operation from theft, abuse, or attacks.
What are examples of security threats?
Unauthorised access, exploitation, denial of service, trojans, eavesdropping, and spoofing.
How can security be modeled?
Through abuse cases and threat analysis, complementing cybersecurity measures.
What is the best security for a system?
A private, isolated network, though impractical for public use due to networking needs.
What are historical approaches to security?
Zones of security, barriers, gateways, and lessons from physical defenses like castles.
What are modern cybersecurity layers?
Firewalls, security zones, encryption, certification, and monitoring to defend against attacks.
What is the role of a firewall?
Hardware/software acting as a barrier between internal and external networks to prevent invasions.
What are examples of security zones?
Levels of access based on public accessibility and the value of secured assets.
What is an abuse case?
A use case identifying actions of ‘bad actors’ to reduce their reward and increase their effort.
What are the five principles of secure system design?
- Establish context; 2. Make compromise difficult; 3. Make disruption difficult; 4. Detect compromise easily; 5. Reduce impact of compromise.
How does cybersecurity balance access and vulnerabilities?
More networking increases access but also introduces vulnerabilities; security balances these concerns.
What is an example of a real-world cyber attack?
A Russian attack on NHS provider Synnovis disrupted services, canceling 10,000+ appointments and postponing operations.
