Network Security

Overview

Network security protects data in transit and limits unauthorized access through segmentation, filtering, and encrypted channels.

Core Controls

• Segmented network zones
• Ingress and egress filtering
• DDoS protection layers
• Secure service-to-service communication

flowchart TD
    A[Internet] --> B[WAF and Edge]
    B --> C[Public Services]
    C --> D[Private Services]
    D --> E[Data Tier]

Practical Example

A standard pattern uses private subnets for databases and allows access only from application subnet security groups.

Production Example

Financial systems often combine firewall rules, private networking, and service mesh mTLS to protect internal communication.

Common Pitfalls

• Flat networks with broad trust zones
• Missing outbound traffic restrictions
• Unmonitored security group drift

Key Takeaways

• Network segmentation is a foundational security control.
• Both ingress and egress controls are required.
• Continuous policy review prevents drift and exposure.