Software Engineering Multiple Choice Questions on “Dependability and Security Specification”.
1. How many stages are there in Risk-driven requirements specification?
a) three
b) four
c) five
d) six
Answer: b
Clarification: These include Risk identification, Risk analysis, Risk reduction and Risk decomposition
2. Consider a case where the system is unavailable and cannot deliver its services to users. What type of failure is being described here?
a) Loss of service
b) Incorrect service delivery
c) System/data corruption
d) None of the mentioned
Answer: a
Clarification: One may separate this into loss of critical services and loss of non-critical services, where the consequences of a failure in non-critical services are less than the consequences of critical service failure.
3. Consider a case where the failure of the system causes damage to the system itself or it data. What type of failure is being described here?
a) Loss of service
b) Incorrect service delivery
c) System/data corruption
d) None of the mentioned
Answer: c
Clarification: None.
4. POFOD stands for
a) Possibility of failure of data
b) Probability of failure of data
c) Possibility of failure on demand
d) Probability of failure on demand
Answer: d
Clarification: None.
5. Which reliability metric sets out the probable number of system failures that are likely to be observed relative to a certain time period?
a) POFOD
b) ROCOF
c) AVAIL
d) None of the mentioned
Answer: b
Clarification: Rate of occurrence of failures (ROCOF) sets out the probable number of system failures that are likely to be observed relative to the number of system executions.
6. Which of the following is not a functional reliability requirement for a system?
a) Checking requirements
b) Recovery requirements
c) Redundancy requirements
d) Ambiguous requirements
Answer: d
Clarification: All the options are correct except option d.
7. To specify security requirements, one should identify the risks that are to be dealt with.
a) True
b) False
Answer: b
Clarification: To specify security requirements, one should identify the assets that are to be dealt with.
8. The aim of preliminary risk analysis and assessment process is to derive security requirements for the system as a whole.
a) True
b) False
Answer: a
Clarification: In preliminary risk analysis stage, decisions on the detailed system requirements, the system design, or the implementation technology have not been made.
9. At which stage of risk analysis specification, the additional security requirements take account of the technologies used in building the system and system design and implementation decisions?
a) Preliminary risk analysis
b) Life-cycle risk analysis
c) Operational risk analysis
d) All of the mentioned
Answer: b
Clarification: This risk assessment takes place during the system development life cycle after design choices have been made..
10. Which reliability requirements are concerned with maintaining copies of the system?
a) Checking requirements
b) Recovery requirements
c) Redundancy requirements
d) Ambiguous requirements
Answer: b
Clarification: These requirements are geared to helping the system recover after a failure has occurred.