Architectural Patterns (Overview)

This article is a definition of terms for important architectural patterns – including exam questions and tags.

In a Nutshell

Architectural patterns offer proven structural concepts for recurring requirements: clear layer separation, loose coupling, or service orientation.

Compact Technical Description

Architectural patterns define how components are organized and connected. The goal is reusability, maintainability, and extensibility.

Typical patterns:

• Layered model (e.g., 3-Tier)
• MVC
• Client-Server
• SOA
• Microservices
• Event-driven Architecture
• Hexagonal Architecture
• Monolith

Exam-Relevant Key Points

• Patterns are “system structure at a high level”
• Support modularity/testability
• Layered model is IHK-relevant
• MVC separates UI responsibilities
• Microservices increase complexity (security/operations)
• Architecture influences costs
• Documentation with diagrams + interfaces + rationale

Core Components

1. Layered Model
2. MVC
3. Client-Server
4. SOA
5. Microservices
6. EDA
7. Hexagonal
8. Monolith
9. Hybrid Architectures
10. Documentation (C4/UML)

Practical Example (3 Layers)

Presentation (HTML/JS)
Business (REST-Service)
Data Access (ORM/DB)

Advantages and Disadvantages

Advantages

• Clearer structure
• Better maintainability/testability
• More flexible technology decisions

Disadvantages

• Overhead with overly complex patterns
• Performance loss with excessive decoupling

Typical Exam Questions (with Short Answer)

1. What is an architectural pattern? Standardized structural concept for software.
2. What layers does 3-Tier have? Presentation, logic, data access.
3. When are microservices useful? In large systems with frequent releases.

Further Information

1. https://arc42.org/
2. https://c4model.com/