Day-22 - Understanding Authentication & Authorization inside Kubernetes 🔐

Key Concepts:
🪪 Authentication (Who are you?)
Verifies your identity using certificates, tokens, or kubeconfig files.
🛡️ Authorization (What can you do?)
Once identified, Kubernetes checks if you’re allowed to perform the requested action.

Types of Authorization in Kubernetes:
1️⃣ ABAC (Attribute-Based Access Control)
Permissions defined in a policy file.
Requires API server restart — not ideal for production.
2️⃣ RBAC (Role-Based Access Control):
Assigns permissions via roles & role bindings.
Scalable, flexible, and the most commonly used method today.
3️⃣ Node Authorization:
Grants permissions to kubelets (nodes) to perform actions for the pods running on them.
4️⃣ Webhook Authorization:
Uses external systems like OPA (Open Policy Agent) for advanced policy control — dynamic and powerful.

Key Learning:
Kubernetes uses a layered approach for access control — combining Node + RBAC + Webhook modes ensures secure, dynamic, and production-ready authorization

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