Shared Responsibility and the Security Map

Where the AWS line sits and what stands behind it: shared responsibility service by service (EC2, Lambda, Fargate, RDS, S3), every in-scope security service placed on one board by the job it does, and the layered, blast-radius thinking the exam rewards.

Content current as of 2026-10.

Lessons

1. Shared responsibility, service by service
2. The security service map
3. Defense in depth and blast radius

Sources

• AWS shared responsibility model
• SCS-C03 exam guide — In-Scope AWS Services
• AWS Well-Architected Framework — security pillar
• SCS-C03 exam guide