New Angle to look at SOA...

--- essence from Ganesh Prasad's Practical SOA 

Among numerous trends that has struck the IT industry, SOA holds an important place. Service Oriented Architecture has been a buzz word, for a certain period of time. Most of the enterprises and businesses proudly announce that they "MOVE to SOA"; or their "Business is SOA compliant". But when we take a look at their implementation, still it resides in the complex, spaghetti kind of set up. This complexity and non SOA existence can majorly cause

• performance drawbacks
• single point of failure

 If a proper SOA implementation has been executed, it ideally should have

• loosely coupled components
• good governance
• re-usability of components

In a proper SOA architecture, there are 3 main lego blocks namely

• Service Container
• Message Broker
• Process Coordinator 

Service container - Holds the service logic (eg: WSO2 AS)

Process Coordinator - Run time / dynamic process evaluations based on state is handled here. (eg: WSO2 BPS)

Broker - Acts as an adapter, mediator and transformer. Sits in between two applications perform the tasks. (eg: WSO2 ESB)

In any kind of complex deployment environment, first it should be clearly identified what is needed where, out of the above 3 main components.

When the coarse grain analysis is over, in the fine grain analysis, supporting SOA elements such as Rule components, Data services components, Presentation components, Governance components, Registry/repository components etc. can be identified and then deploy the relevant systems appropriately. 

SOA is NOT EASY. But SIMPLE. So plan well & handle with care.