What is an ESB and why would you use one?

Most organizations have multiple generations of systems: legacy systems and mainframes, databases, enterprise applications, and increasingly cloud and SaaS applications and mobile applications.  Delivering business results requires integrating between all of these heterogenous systems.  

A series of ad hoc integrations between these applications is brittle and expensive to maintain.  It delivers poor reuse and fails to keep up with new projects and business challenges.  An ESB acts as a transit system for carrying data between applications, simplifying the process of maintaining integrations and making future changes less expensive and time consuming.

Some key ESB benefits include:

• Facilitates a flexible and extensible architecture to grow and change as business needs change
• Easily scale infrastructure without impact to code
• Seperates business logic from protocols and message formats for faster and more nimble development
• Provides consistent management, monitoring and security across integrations

Service Mediation	Message Routing
Separate business logic from messaging Shield services from message formats and protocols Enable location-independent service calls Provides protocol bridging	Route messages based on content and complex rules Filter, aggregate and re-sequence messages
Data Transformation	Service creation & hosting
Exchange data across applications with varying data formats Manipulate message payload, including encryption, compression and encoding transformations Format messages across heterogeneous transport protocols data types	Expose end-points, EJBs, Spring beans, and POJOs as services Host services as a lightweight service container
Service Orchestration
Create message flows with lightweight orchestration capabilities

Mule ESB

With over 2500 production deployments s including 5 of the world’s top 10 banks and over 35% of the Global 500, Mule is the world's most widely used Enterprise Service Bus.  Unlike other ESBs, Mule is lightweight, letting programmers be productive in minutes.  With Mule ESB, there is no need to embark on a top-down transformative SOA initiative with a lengthy payback horizon.  While Mule is lightweight and flexible, adapting to your existing infrastructure, it is also robust enough to power even the largest and most demanding enterprise SOA implementations.