1 - Requirements in Context
Every cloud project starts with requirements. In this episode, Chris explores the critical pillars of cloud architecture: resilience, scalability, performance, and cost—and why defining them upfront (before drawing any architecture diagram) is essential.
What You’ll Learn
- Why requirements engineering is the foundation of any cloud architecture project
- Key resilience metrics: SLA, RTO (Recovery Time Objective), RPO (Recovery Point Objective), MTTR (Mean Time to Recovery), and MTBF (Mean Time Between Failures)
- How composite SLAs differ from looking at the weakest link in your architecture
- The relationship between availability tiers (e.g., 99.9% vs 99.999%) and real-world downtime allowances
- How scalability, performance, and cost form trade-off dimensions in every architecture decision
- Why over-engineering for loosely-defined requirements leads to unnecessary cost and complexity
Key Concepts
This episode maps on-premises thinking (racks, data centres, zones, regions) to equivalent cloud failure domains, helping architects understand how availability requirements translate when moving to the cloud. Cost is introduced as a first-class design dimension—not a post-hoc optimisation—and the importance of composite SLAs over single-component SLA views is highlighted throughout.
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