Security Control Implementation

3.8.1 Defense in Depth

Don't rely on single security controls. Layer defenses:

Example Layered Approach:

1. Network firewall (perimeter)
2. Device authentication (access)
3. Encryption (data protection)
4. Audit logging (detection)
5. Incident response (recovery)

3.8.2 Secure by Design Principles

Least Privilege: Give minimum necessary access

• Users get only needed functions
• Processes run with minimal rights
• Services have restricted permissions

Fail Secure: Safe behavior during failures

• Device enters safe state on error
• Denies access when uncertain
• Maintains critical functions

Defense in Depth: Multiple security layers

• Don't rely on single control
• Overlapping protections
• Diverse defense mechanisms

Simplicity: Complex = vulnerable

• Minimize attack surface
• Reduce feature creep
• Clear security boundaries

3.8.3 Common Security Patterns

Secure Boot:

• Verify bootloader integrity
• Check kernel signature
• Validate application code
• Establish chain of trust

Secure Communication:

• TLS for network traffic
• Certificate validation
• Perfect forward secrecy
• Protocol downgrade prevention

Access Control:

• Multi-factor authentication
• Role-based permissions
• Session management
• Account lockouts