Part 2

Question 1

• It equates to its trustworthiness
• Is a system that is trusted by its users

Answer 1

Dependability

Question 2

Principal Dimensions of Dependability

Answer 2

1. Availability
2. Reliability
3. Safety
4. Security

Question 3

Reflects the extent to which the system can be repaired in the event of a failure

Answer 3

Repairability

Question 4

Reflects the extent to which the system can be adapted to new requirements

Answer 4

Maintainability

Question 5

Reflects the extent to which the system can deliver services whilst under hostile attack

Answer 5

Survivability

Question 6

Reflects the extent to which user input errors can be avoided and tolerated

Answer 6

Error Tolerance

Question 7

Other Dependability Properties

Answer 7

1. Repairability
2. Maintainability
3. Survivability
4. Error Tolerance

Question 8

A system attribute that is concerned with the ease of repairing the system after a failure has been discovered or changing the system to include new features

Answer 8

MAINTAINABILITY

Question 9

The ability of a system to continue to deliver its services to users in the face of deliberate or accidental attack

Answer 9

SURVIVABILITY

Question 10

Tend to increase exponentially as increasing levels of dependability are required

Answer 10

Dependability Costs