Foundations & Mental Models

Why Foundations Matter

Most developers jump straight into provisioning EC2 instances or Lambda functions without understanding the underlying physical constraints of cloud computing.

When you design on AWS, every architectural choice is bound by:

1. The Speed of Light & Network Latency: Cross-AZ latency (~1-2ms) vs Cross-Region latency (~50-120ms).
2. Failure Domains: A process will crash, an instance will fail, and an entire Availability Zone can lose power. Resiliency means designing so that isolated failures do not cause catastrophic outages.
3. The Shared Responsibility Model: AWS manages the security OF the cloud (physical data centers, hypervisors, core network); you are 100% responsible for security IN the cloud (IAM policies, encryption, OS patches, data firewalls).
4. The Cost Velocity: Unlike on-premise hardware where CapEx is fixed, cloud OpEx can scale uncontrollably within hours if recursive loops or unthrottled queues are deployed.

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The Well-Architected Framework: The 6 Pillars

Throughout every case study in this academy, architectures are evaluated against AWS’s 6 core pillars:

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Case Studies in This Module

Explore the following hands-on case studies to solidify these mental models:

1. Case Study Methodology: How to deconstruct real enterprise architectures from business requirements.
2. Free-Tier & Budget Trap Guard: Setting up automated billing circuit breakers and anomaly alerts.
3. Diagram Literacy & Subnet Mappings: Translating logical architecture diagrams into physical VPC networks.