Thursday, May 10, 2007

Service Hierarchy

It was during my regular read from home to work when I came across this idea of Service Hierarchy in an Enterprise Application (for that matter any application). I was reading the book "Extending Web Services Technologies - The Use of Multi-Agent Appproaches" published by Springer.

While in general sense the Services (Web-Services) are classified as Simple and Composite, but in reality there are many sub-classifications possible. On top level there are only two types but the nature of complexity varies in Composite services.

In the diagram above I tried to represent how the services (functionalities) build on the top of simple ones in an Enterprise Information System. The simple services like Create, Save, Update and Delete are at the bottom of the hierarchy. The layer 2 services use the basic ones to meet their functional requirement. Layer 3 builds on the top of layer 2 and so on.

While simple services are piece of software which performs a smaller task. A composite service is the one which is build by assembling and accessing multiple services (possibly from multiple service providers).

This draws our attention to next issue which is Service Composition and Service Oriented Computing (SOC). In the next post will discuss in detail about the Service Oriented Computing.

Until Next Time....:)