U3's Couch

When someone ask me what is Microsoft ESB, I told him the usual definition and I explain it using the terms of SOA and SOI. His face had been changed to this:

So before taking about what is ESB lets explain some important definitions :

What is Infrastructure?
The fundamental structure of a system or organization. The basic, fundamental architecture of any system (electronic, mechanical, social, political, etc.) determines how it functions and how flexible it is to meet future requirements.

So what is the Service Orientation in general?
Service-orientation is a service paradigm that specifies the creation of automation logic in the form of services. It is applied as a strategic goal in developing a service-oriented architecture (SOA). Like other design paradigms, service-orientation provides a means of achieving a separation of concerns.

Okay what is Service Oriented Infrastructure?
Essentially, an SOI is a set of physical and system software level IT resources, which are geared to meeting the demands of an SOA-defined application environment, and in many ways mirrors the attributes that are commonly associated with SOA environments.

Ummmmmmm… Is there is a different between Service Oriented and Object Oriented design?
First lets define what is Object Oriented Design is part of OO methodology and it forces programmers to think in terms of objects, rather than procedures, when they plan their code. An object contains encapsulated data and procedures grouped together to represent an entity.

So Service-oriented programming (SOP) builds on top of OOP, allowing services to be built using OO techniques. These services themselves provide increased reuse of the business logic, by allowing the service to be used in diverse applications. OOP focuses on what objects an application consists of, while an SOP approach focuses on the application's functionality, or in other words, what the application does.

then the term of ESB is:

the context of implementing an infrastructure for enabling a Service-Oriented Architecture (SOA). However, real-world experience with the deployment of SOAs has shown that an ESB is only one of many building blocks that make up a comprehensive Service-Oriented Infrastructure (SOI). The term ESB has morphed in a number of different directions, and its definition depends on the interpretation of individual ESB and integration platform vendors, and on the requirements of particular SOA initiatives.

Based on the experience Microsoft has gathered from many successful real-world SOI implementations, you can think of an Enterprise Service Bus as a collection of architectural patterns based on traditional enterprise application integration (EAI), message-oriented middleware, Web services, .NET and Java interoperability, host system integration, and interoperability with service registries and asset repositories.

Okai , So What ?!

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