Enterprise Service Buses

An enterprise service bus, or ESB, is an integration architecture that places a shared mediation layer between systems. Instead of application A maintaining a separate protocol, endpoint, and data translation for every partner, each system connects to the bus through an adapter or service interface.

The bus can route a message, translate its format, apply security, call an endpoint, and record operational evidence. This is valuable when an organization has many long-lived systems with different protocols and data models. It is also a centralization risk. A bus that owns business decisions or becomes the only route for every change can turn into a bottleneck.

The mental model