Session 03

• Categorization of Quality Attributes

  • Operational

  • Structural

  • Cross-Cutting

• Least Worst Combination of Trade-offs

• Availability

  • Fault - Failure

  • Fault-related concerns

    • Risks associated with Faults

      • Minor

      • Major

      • Critical -> Disasters

    • Frequency

  • Responses to Faults

    • Prevent

    • Tolerate

    • Remove

    • Forecast

  • Availability General Scenario

    • Source -> Internal, External

    • Stimulus -> Fault

    • Artifacts -> (Processor, Storage, Communication Channel, etc.)

    • Environment -> (Normal, Overloaded, Special Occasions, Degraded, etc.)

    • Response -> (Prevent, Detect, Recover, etc.)

  • Occasionally Connected Systems

  • SLA (Service-Level Agreement)

    • Service-Level Failure

  • Tactics for Availability

    • Detection

      • Monitoring, Ping, Health Checks, etc.

      • Condition Monitoring -> Assumptions, Edge Cases

      • Tests, Checks, Validations

    • Prevention

    • Recovery