Event-Driven Application Design

I need a comprehensive application design based on technical specifications. The design should cover:

- System Architecture: Event-driven model.
- Data Architecture: Relational database setup.
- Security Architecture: Must include encryption, access control, and audit logging.

Ideal skills and experience:
- Proven expertise in event-driven system design.
- Strong background in relational database architecture.
- In-depth knowledge of security protocols, especially encryption, access control, and audit logging.

Please provide detailed and well-structured designs to facilitate the next phases.