Web services and business services are two hot topics today, but many companies fail to appreciate the difference. As a result, they can fall into a nasty trap, particularly mainframe-oriented companies.
A Web service is a piece of business logic that can be invoked and executed in a standard fashion, using Simple Object Access Protocol (SOAP) as a communications protocol and Web Services Description Language (WSDL) as the specification language.
A business service is a reusable combination of IT components that delivers a business-oriented service -- for instance, "Get Customer Details" -- to the caller, at the same time shielding the caller from any of the implementation details of that service. At first glance, these two definitions seem awfully similar, but the key difference is the choice of granularity of the two types of services.
