Getting started with SOA

An important matter when we are thinking of SOA adoption is to know how to get started. At this stage many questions come to our minds and if we don't have someone with experience to show us the way, could be a big challange to understand the whole concept of SOA and apply it in real life. This article aims to give you a overall guideline showing how you can quickly get started.

The transition to SOA can be addressed in many different ways, it all depends on how mature is your company's IT, as well as the reasons for adopting SOA. A SOA adoption can be thought of as continuum with four broad levels, and each level you reach will bring you better business value.

1. Implementing individual web services. In this level companies create web services from tasks in existing or new applications.
2. Service oriented integration of business functions. In this level, companies integrate two or more applications using web services or other service oriented architectures.
3. Enterprise wide IT transformation. In this level, companies can use SOA as their standard for exposing application functions; companies are able to use SOA to integrate to any application.
4. On demand business transformation. In this level, companies are able to change their software and partners quickly in order to meet the changing needs of the business.

 Let's now detail each of the previous levels, showing ways of putting them in practice:

Level 1

• Exposing functions of an existing application as web services.
• Creating a new application using web services from another application.
• Creating a new application that contains web services and uses those web services. 

Level 2

• Analyzing two applications in order to determine what services are needed.
• Choose SOA infrastructure and tools, creating standards, and so forth

At this level governance is becoming important.

Level 3 and 4 

When starting with enterprise wide IT transformation or on demand business transformation, governance and executive buy-in are critical. Starting at this level is usually part of a strategic transformation of business that involves analyzing the company's current state, the company's strategy, the company's IT systems, the trends in the company's industry, and technology trends.

Transitions that start at these top two levels frequently involve many steps and include steps to verify assumptions and validate decisions made in previous steps. These verifications can include reviews by experts, as well as testable prototypes for measuring quality of service factors such as performance and usability.

That's all folks, hope this article can help you to get started with SOA in your company!

Bye!


Source:
VW003 - Introducing the Value and Governance Model of Service-Oriented Architecture, IBM Corporation, 2007.