An ESB is an architecture for connecting and integrating enterprise systems. An ESB may also connect to partner and customer systems. As Figure 1 shows, each system in the enterprise connects to the ESB and communicates through it. The connections between systems are determined by how the ESB has been configured. Instead of directly connecting programs, they communicate through a common messaging fabric.
An ESB is a convergence of EAI, MOM, and SOA concepts and techniques, embodying the best practices from each discipline.
Enterprise Application Integration
An ESB integrates with legacy systems using application specific adapters.
Message Oriented Middleware
An ESB provides intelligent routing, such as publish-subscribe, message brokering, and failover routing. An ESB mediates data, communication, and security differences between applications.
An ESB is based on open standards such as XML, SOAP, and WS-*. An ESB provides the necessary infrastructure to create and manage a service oriented architecture.
An ESB provides logical centralized management but is physically decentralized. An ESB is able to monitor activity and throttle activity as per a Service Level Agreement ( SLA ).
ESBs provide the following business benefits:
- Improve business agility
- Streamline business execution
- Expand business intelligence
- Decrease costs
ESBs provide the following I.T. benefits:
- Increase flexibility
- Lower total cost of ownership
- Strengthen operational reliability
- Heighten manageability
- Decrease risk