Cloud value proposition
- Six advantages of cloud: trade capital expense for variable expense; benefit from massive economies of scale; stop guessing capacity; increase speed and agility; stop spending on running data centres; go global in minutes.
- Elasticity = scale capacity automatically with demand. Availability = stays up. Fault tolerance = keeps working correctly through component failure. Agility = ship faster.
- Well-Architected Framework has six pillars: Operational Excellence, Security, Reliability, Performance Efficiency, Cost Optimization, Sustainability.
Global infrastructure
- Region = a geographic area; each Region has multiple, isolated Availability Zones (AZs). Deploy across AZs for high availability.
- Edge locations serve CloudFront (CDN) and Route 53 close to users. Local Zones and Outposts push compute closer to specific metros / on-premises.
- You choose a Region for latency, price, compliance/data-residency, and service availability.
Core services by category
- Compute: EC2 (VMs), Lambda (serverless functions), ECS/EKS (containers), Elastic Beanstalk (managed app platform).
- Storage: S3 (object), EBS (block, attached to EC2), EFS (shared file), S3 Glacier (archive).
- Database: RDS (managed relational), Aurora (AWS-built relational), DynamoDB (managed NoSQL), Redshift (data warehouse), ElastiCache (in-memory).
- Networking: VPC (private network), Route 53 (DNS), CloudFront (CDN), Direct Connect (dedicated line), API Gateway.
Security and the shared-responsibility model
- AWS is responsible for security OF the cloud (hardware, the global infrastructure, managed-service software). The customer is responsible for security IN the cloud (data, IAM configuration, OS patching on EC2, network rules).
- IAM: users, groups, roles, policies. Grant least privilege; prefer roles over long-lived access keys; protect the root user with MFA and don't use it day-to-day.
- Detective / protective services: CloudTrail (API audit log), CloudWatch (metrics and logs), GuardDuty (threat detection), Shield (DDoS), WAF (web filtering), KMS (key management), Artifact (compliance reports).
Billing, pricing, and support
- You pay for compute, storage, and data transfer OUT of AWS. Inbound data transfer is generally free.
- EC2 purchase options: On-Demand (no commitment), Savings Plans / Reserved Instances (commit for a discount), Spot (spare capacity, deep discount, can be reclaimed), Dedicated Hosts.
- Cost tools: AWS Pricing Calculator (estimate before you build), Cost Explorer (analyse spend), AWS Budgets (alert on thresholds), Cost and Usage Report (line-item detail), Trusted Advisor (cost / security / performance checks).
- Support plans: Basic (free), Developer, Business, Enterprise On-Ramp, Enterprise — response times and access to a Technical Account Manager scale up with the tier.
Test yourself on CLF-C02
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