This presentation describe the importance of trade-off between software architecture quality attribute (NFR). Explain about Performance, Security, Availability and Scalability in depth and other in briefly. Presented on tech talk @ DFN Technology.

1. Software Architecture Quality Attributes
Tradeoffs
Presented By : Asanka Dilruk

2. Diff. Product Domains
Houses Vehicles Software

3. Reliability
Adaptability
Affordability

4. Tradeoff
• As a Philosophy Theory
• Define Tradeoffs at Beginning
o ATAM
o Utility Tree (Quality Attribute Metrics)
• Architecture should able to balance Attributes

5. Performance
• Metrics
o TPS, Response Time ,Latency/Waiting Time
• Tactics
o Maximum resource utilization
o Parallelism
o Avoid unnecessary message conversions
• Tradeoffs
o Security, Availability, Testability, Reliability

6. Availability
• Metrics
o Percentage (MTTF / MTTF + MTTR)
o 90% (40 Days), 99%(4 Days), 99.9%(9 Hours), 99.99% (50 Minutes), 99.999% (5 Minutes)
• Tactics
o Replication (Multiple do same)
o Recovery Mechanism
o Fault Tolerance
• Tradeoffs
o Security, Testability, Cost

7. Security
• Metrics
o Measurement of confidentiality, integrity & availability
• Tactics
o Prevention, Detection, Reaction
o Information can be in Being transmitted, Being stored or Being processed
o Identification, Authentication, Access Control, Auditing, Encryption, Hashing, Cryptography
• Tradeoffs
o Performance, Accessibility, Usability, Cost

8. Scalability
• Metrics
o Throughput against the resources
o VS & HS
• Tactics
o Maximum resource utilization (VS)
o Distributed systems
o Load balancing (SW/HW)
• Tradeoffs
o Security, Testability, Deployability

9. Reliability
Affordability

10. Thank You !

11. Discussions