Loosely Coupled Use Cases Models

This article from Willem Van Galen outlines a standard approach for representing basic event-driven architecture (EDA) aspects in system use case models. He explains that there are two ways where use cases can be coupled: command-and-control and publish-and-subscribe. The article introduces the concept of Event Manager and describes the Event Manager use cases. His conclusion is that systems analysts have two distinct patterns available to logically model how system processes (system use cases) are related: tightly coupled or loosely coupled.