Glossary · System coordination, integration and orchestration
Enterprise service bus (ESB)
Also known as: ESB, service bus
German: Enterprise Service Bus (ESB)
In enterprise integration, an enterprise service bus (ESB) is a middleware architecture in which applications communicate through a common integration infrastructure that provides message routing, transformation, protocol mediation and service orchestration.
- System integration
In one sentence
An enterprise service bus is integration middleware that routes, transforms and mediates messages between applications through a shared infrastructure.
Example
The ESB receives production confirmations from the MES, transforms them into the ERP's format and routes copies to the quality system and the data warehouse.
How it applies
- Architecture: An ESB centralizes integration logic and replaces point-to-point interfaces. Many organizations have moved toward lighter integration platforms and event brokers, but ESBs remain common in established IT landscapes.
- Engineering: Keep business logic out of the bus where possible. An ESB overloaded with rules becomes a hard-to-change central bottleneck.
- Documentation: Document each integration flow on the bus: source, target, mappings, routing rules, error handling and owner. Without this, the ESB turns into a black box that nobody dares to change.
ESB vs. event broker
An ESB typically provides transformation, routing and orchestration in the middleware. An Event broker mainly distributes events between producers and consumers and leaves transformation to the endpoints or separate services.