1. Architecture Analysis Techniques
Ding Li 1

2. Review 2

3. Inspections and Reviews
Manual Techniques
Static or Scenario-based
In Theory, it can test everything of an architecture
All stakeholders are involved
Not only technical people 3 3

4. the Architectural Trade-off Analysis Method
First proposed by Clements in CMU
Human-centric process to identify risks in the early stage of software design
All stakeholders will be involved
Clients
Managers
Developers 4

5. ATAM Focus on non-functional properties Identify risks
Modifiability
Security
Performance
Reliability
Identify risks
Reveal how well the system meets the requirements
System level
Completeness, Capability, Correctness 5 5

6. Detail of ATAM 4 Phases 9 steps Preparation Presentation and Analysis
Testing and Reporting
Finalization
9 steps 6

7. Phase 0-Preparation Find out the right people Training Session
Who will do the presentation
Who will be the representatives of clients
Training Session
Necessary Materials
Kick-off Meeting 7

8. Phase 1-Presentation and Analysis
Step 1:Present the ATAM
Step 2:Present the business drivers
Step 3:Present the architecture
Step 4:Identify the Architectural Approaches
Step 5: Draw the Quality Attribute Utility Tree
Step 6:Analyze the Architectural Approach
Step 3: Should include constrains, systems to interact and styles and patterns
Step 4: the evaluate team will ask the Architects to explicitly name any identifiable approaches
Step 6: understand the details and how it was applied in system, well-known weakness, trade- offs, compare with other approach for each scenarios in Step 5. 8 8

9. Phase 2-Testing and Reporting
Step 7: Brainstorming and Prioritizing Scenarios
Step 8: Analyze the Architectural Approach
Step 9: Present the result
Step 7 more stakeholders are involved 9 9

10. Phase 3- Finalize Producing a final report
Collecting Data for measurement and improvement
Archive all artifacts 10

11. Why use the ATAM?
Enable non-technical people to control the quality of software
A Method for developers to sell their project
Does the project worth the money?
Persuade the clients to go on give you money
For example, my mother wants to develop a students information system 11 11

12. Limitation of ATAM
Expensive
Time consuming
Human intensive 12

13. Model Based Analysis Based on the description of Architecture
ADLs
Can be done automatically
Less expensive 13

14. Model Based Analysis Goals Scope Type Static Consistency Compatibility
Internal Completeness
Scope
Component level
Data exchange level
Type
Static 14

15. Model Based Analysis Techniques are complex
May not be possible to analyze a very large system in a very high accuracy
Sometimes may need to sacrifice some accuracy
Can only analyze properties that are not formally described
Non-functional Properties are not supported
For example, in our homework, we may need to enumerate all paths in the Graph, 15 15

16. Model Based Analysis Enabled by ADLs
type DataStore be interface
action in SetValues();
out NotifyNewValues();
behavior
begin
SetValues => NotifyNewValues();;
end DataStore;
type Calculation is interface
action in SetBurnRate();
out DoSetValues();
action CalcNewState();
SetBurnRate => CalcNewState1(); DoSetValues(a);;
end Calculation;
type Player is interface
action out DoSetBurnRate();
in NotifyNewValues();
TurnsRemaining : var integer := 1;
action UpdateStatusDisplay();
action Done();
Parsers and compilers
Check the syntax
Check consistency
Exam Refinement
Exam Constrains 16

17. Simulation-Based Analysis
Create a dynamic executable model of system
It is a high level executable model
Require support from modeling language, not all languages are executable 17

18. Simulation-Based Analysis
Goals
Completeness
Consistency
Compatibility
Correctness
Scope
System or subsystem level
Dataflow 18

19. Simulation-Based Analysis
Concern
Behaviors
Interaction
Non-functional properties
Dynamic, scenario-based
Fully automated 19

20. XTEAM Is developed by George Edwards
Create simulation codes from High-level model
Easy to change the model and create new simulation codes
Can simulate the latency, power consumption and reliability of a system 20

21. XTEAM Toolchain 21

22. Meta-model in XTEAM 22

23. xADL in XTEAM 23

24. FSP in XTEAM FSP is a behaviors ADL
Present Finite State Machine in an algebra way 24

25. Power simulation in XTEAM
Assign the Power consumption of each process
Assigned by Power model
Assigned by Domain Expert
Record the power consumption of each invocation of process
Data are analyzed by human

26. Summary of XTEAM Fully automatic simulation
Generate simulation code automatically
Human are only involved in Data analysis
A wider range of goals and concerns and be achieved than static techniques
Could analysis some non-functional properties 26

27. Reliability Analysis
The probability that the system runs without failure
A failure is the occurrence of an incorrect output according to an input
Error: mental mistake made by programmers
Fault: manifestation of an error
An abnormal condition that may cause a reduction in, or loss of, the capability of a component to perform a required function
A requirements, design, or implementation flaw or deviation from a desired or intended state 27 27

28. Reliability Metrics Time to failure Time to repair
Time between failures 28

29. Discrete Markov Model A Stochastic Process Model
Based on a Finite State Machine 29

30. Hidden Markov Process
Transition Probabilities between each state may not be known
Need some training data to estimate transition probabilities
Simulation is needed 30

31. Summary of Reliability Analysis
Reliability analysis can be both dynamic or static
Require Domain Knowledge
Some times the Markov properties may not satisfied 31

32. Summary ATAM Model-based Analysis Simulation-based Analysis
Reliability Analysis 32

33. Reference Evaluating Software Architecture: Methods and Case Studies
Guide to the Rapide-1.0 Language Reference Manuals
Rapide-1.0 Architecture Language Reference Manual
OMG Object Constraint Language (OCL) Documents
DRESDEN OCL MANUAL FOR INSTALLATION, USE AND DEVELOPMENT
Model and Object Verification by Using Dresden OCL Birgit Demuth et.al 2009
XTEAM USER MANUAL
Finite State Process Algebra and LTSA
Scenario-Driven Dynamic Analysis of Distributed Architectures George Edwards et.al 2007
Estimating Software Component Reliability by Leveraging Architectural Models Roshanak Roshandel et.al 2006 33