Describing a Logical Application System
A logical application is an element of the IT architecture.

A logical application is a component of an application that is available to the end user of this application in the context of his/her work. Logical applications represent the split of an application into its basic functional units. A logical application is a consistent, indivisible unit of processing that coordinates a set of messages and events in order to perform a task in the information system. In the application system, the logical application is the most basic functional unit.
A logical application system is a component used to describe the organization of logical applications according to a service-oriented approach.

A logical application system is an assembly of other logical application systems, logical applications and end users interacting with application components to implement one or several functions.

In HOPEX System Oriented IT Architecture, there is no direct link between an application system and a logical application system.