1. Methodology for Architectural Level Reliability Risk Analysis
Lalitha Krothapalli
CSC 532

2. Risk Risk is a combination of two factors.
Probability of malfunctioning( failure)
Consequence of malfunctioning (severity)

3. Uses of Risk Assessment
Finding out the complex modules.
Finding out the potentially troublesome modules.
Calculates the effort for testing.

4. Types of Risks Availability Risk. Acceptance Risk. Performance Risk.
Cost Risk.
Schedule Risk
Reliability Risk.

5. Components: Like objects, classes or procedures.
Architectural level
System is divided in to two parts
Components: Like objects, classes or procedures.
Connectors: Procedural calls , Client server protocols

6. Advantage of Architectural Risk Analysis
Early detection and correction of errors
Cost will be less.
Design and coding are also depend on the complexity of the architecture.

7. Advantages of simulating the Architecture Model
Obtain dynamic behavior of components and connectors using dynamic metrics.
Study the consequences of failure and severity of that failure.

8. Background The proposed methodology is based on the previous work of
Dynamic Metrics
Reliability Modeling and Analysis of Software Architecture

9. Dynamic Metrics Used to find out the complexity of each component
Executive components have lot of state changes
Measures the impact on the maintainability, reusability and error proneness
Connector complexity can be calculated by using dynamic coupling metrics

10. Component Dependency Graphs
Used to find out the reliability analysis at the architectural level.
Represents components, connectors and component, connector reliabilities
Can be used to calculate the execution time of the components and the interaction between the components

11. Risk Assessment Methodology
Usage of architectural description language for modeling system architecture.
Calculate complexity analysis using simulation of the architecture.
Obtain severity analysis using FEMA and simulation runs.
Developing heuristic risk factors for components and connectors.
Preparing CDGs for calculating risk assessment.

12. Architectural Modeling
Interaction between the components
Behavior of individual components
Real time object oriented model can be used to simulate the architecture

13. Complexity Analysis
Component Complexity
Connector complexity

14. Severity analysis Identifying failure modes.
- failures modes of Individual components.
- failure modes of individual connectors.
Conducting Effect Analysis.
Ranking severity.
Catastrophic
Critical
Marginal
Minor.

15. Develop Reliability Risk Factors for Architecture Elements
Heuristic Factor for a component
Heuristic factor for a connector.

16. Developing Component Dependency Graphs
Calculate the execution time of each scenario.
Calculate the execution time of each component
Calculate the transition probability from one component to other for each and every scenario.
Predict the complexity factor and severity of the index of the each component.

17. Reliability Risk Analysis Algorithm
The risk factor of a system can be obtained from aggregating the risk factors of all components and connectors
Breadth of a graph - All risk factors
Depth of a graph - Sequential execution

18. Conclusion
Applicable to architecture level so the errors can identified and detected at the early stages of life cycle.
Based on dynamic metrics .
Automatable.

19. References
1. Volume: 28,   Issue: 6,   Year: Jun 2002 A methodology for architecture-level reliability risk analysis Yacoub, S.M.; Ammar, H.H. Page(s):
2. 1  Architectural-level risk analysis using UML Goseva-Popstojanova, K.; Hassan, A.; Guedem, A.; Abdelmoez, W.; Nassar, D.E.M.; Ammar, H.; Mili, A.; Software Engineering, IEEE Transactions on , Volume: 29 , Issue: 10 , Oct Pages:946 – 960
3. 7  Risk analysis-a subjective process Redmill, F.; Engineering Management Journal , Volume: 12 , Issue: 2 , April Pages:91 – 96