A well-designed application requires that the logical layers be treated with care during the physical implementation to ensure that as the business evolves, a shift in either the business model or the technology framework won't leave the application in the legacy bin.
The Presentation Services layer will change often in the life span of an application. It is crucial to separate the user interface from the implementation. Today, Web forms; tomorrow, wireless.
The Business Context Services layer is responsible for the syntax and context editing. This logical layer will be implemented in both the user interface component and the Web server.
The Business Rule Services layer is responsible for the many workflow issues that ...