I read a blog post last week that brought up a simple question – What is a service (in SOA terms)?
I have faced a huge amount of confusion over this question throughout the last two or three years, so I decided now was the time to get the answer down in writing! The answer, of course, is that SOA services are BUSINESS services, representing individual business operations. They are not web services. They are not IT programs. In fact, if only we could get the nomenclature straight the confusion probably wouldn’t have arisen. My view is to call IT objects such as programs or transactions ‘components’. SOA services are made up of components orchestrated together to deliver the particular business function. On top of this, SOA composite services can orchestrate together a mixture of components and SOA services.
For anyone interested, there is a Lustratus Insight available from Lustratus at no charge that goes through the arguments in more detail.