ATAM Decision-Making - Mark Heseltine.pdf

Overview of the Architecture Tradeoff Analysis Method (ATAM)

1. Introduction to ATAM
Architecture
Tradeoff
Analysis
Method
http://www.sei.cmu.edu/architecture/tools/evaluate/atam.cfm
Scenario and
requirements
gathering
Develop
architectural
views
Quality
attributes
Tradeoffs
Mark Heseltine
[email protected]

2. Step 1: Requirements
•Framing
•What “good” looks like
•Pre-work, possibly lasting several
weeks
Scenario and
requirements gathering
Develop
architectural views
Quality
attributes
Tradeoffs

3. What good looks like: typical quality attributes
User view
•Performance
•Availability
•Usability
•Security
•Privacy
Developer view
•Maintainability
•Portability
•Reusability
•Testability
•Extensibility
Business
stakeholder view
•Time to market
•Cost/benefits
•Project lifetime
•Marketability
•Risk
Rosenblum & Wolf, 2008

4. Step 2: Develop
scenarios
•Classic white-board exercise
•Develop architectural view for
each alternative
•Best done with technical
stakeholders (ie squads,
engineering leads, developers,
subject matter experts, architects
etc)
Scenario and
requirements gathering
Develop
architectural views
Quality
attributes
Tradeoffs

5. Scenario template
Alternative title
ComponentDeliverRun
Squad 1
Squad 2
Squad 3
Squad 4
T-shirt sizing
Design sketch
ProsCons
Prepared by: technical stakeholders

6. Step 3: Quality
attributes
•Done by the solution architect
•Analyse each scenario
•Focus on how they differ
•Build a table that compares
alternatives and quality measures
Scenario and
requirements gathering
Develop
architectural views
Quality
attributes
Tradeoffs

7. Step 4: Tradeoff
analysis
•Business stakeholder (i.e commercial) exercise
•Make it clear which is the best alternative (be wary of telling them what to do)
•Can usually be solved in a meeting with business stakeholders (e.g. product manager, project manager, business owner, sponsor)
•May also want technical stakeholders there
Scenario and
requirements gathering
Develop
architectural views
Quality
attributes
Tradeoffs

8. Tradeoff example
AlternativePriceQuality
attribute 1
Quality
attribute 2
Quality
Attribute 3
Scenario AXLGoodYesYes
Scenario BMOKMaybeYes
Scenario CSPoorNoNo
Decision with business stakeholders
Prepared by: solution architect

9. ATAM summary
Scenario and requirements
gathering
Develop architectural
views
Quality attributes
Tradeoffs
Business
stakeholders
Technical
stakeholders
StepParticipantsActivity
1. PreparationSolution ArchitectRequirements elicitation
2. Scenario preparationTechnical stakeholders (i.e squads)Whiteboard session(s)
Planning poker
3. Trade-off analysisBusiness stakeholders, technical
stakeholders
Presentation of tradeoffs, discussion
4. Follow-upSolution Architect, project teamCommunicate and record outcomes
Document solution