ALSO CALLED: Enterprise Service Bus and Enterprise Services Bus
DEFINITION: An enterprise service bus (ESB) is a software architecture for middleware that provides fundamental services for more complex architectures. For example, an ESB incorporates the features required to implement a service-oriented architecture (SOA). In a general sense, an ESB can be thought of as a mechanism that manages access to applications and services (especially legacy  … 
Definition continues below.

ESB DEFINITION (continued): …  versions) to present a single, simple, and consistent interface to end-users via Web- or forms-based client-side front ends.

In essence, ESB does for distributed heterogeneous back end services and applications and distributed heterogenous front-end users and information consumers what middleware is really supposed to do: hide complexity, simplify access, allow developers to use generic, canonical forms of query, access and interaction, handling the complex details in the background. The key to ESB's appeal, and possibly also its future success, lies in its ability … 
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