Template Type: Symbols

An application service represents an explicitly defined exposed application behavior.

An application service exposes the functionality of components to their environment. This functionality is accessed through one or more application interfaces. An application service is realized by one or more application functions that are performed by the component. It may require, use, and produce data objects.

An application service should be meaningful from the point of view of the environment; it should provide a unit of behavior that is, in itself, useful to its users. It has a purpose, which states this utility to the environment. This means, for example, that if this environment includes business processes, application services should have business relevance.

A purpose may be associated with an application service. An application service may serve business processes, business functions, business interactions, or application functions. An application function may realize an application service. An application interface may be assigned to an application service. An application service may access data objects. The name of an application service should preferably be a verb ending with “ing”; e.g., “transaction processing”. Also, a name explicitly containing the word “service” may be used.

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An application process represents a sequence of application behaviors that achieves a specific outcome.

An application process describes the internal behavior performed by an application component that is required to realize a set of services. For a (human or automated) consumer the services are relevant and the required behavior is merely a black box, hence the designation “internal”.

An application process may realize application services. Other application services may serve (be used by) an application process. An application process may access data objects. An application component may be assigned to an application process (which means that this component performs the process). The name of an application process should clearly identify a series of application behaviors; e.g., “Claims adjudication process”, or “General ledger update job”.

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An application interface specifies how the functionality of a component can be accessed by other elements. An application interface exposes application services to the environment. The same application service may be exposed through different interfaces, and the same interface may expose multiple services.

In a sense, an application interface specifies a kind of contract that a component exposing this interface must fulfill. This may include parameters, protocols used, pre- and post-conditions, and data formats.

An application interface may be part of an application component through composition, which means that these interfaces are provided by that component, and can serve other application components. An application interface can be assigned to application services, which means that the interface exposes these services to the environment. The name of an application interface should preferably be a noun.

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An application interaction represents a unit of collective application behavior performed by (a collaboration of) two or more application components.

An application interaction describes the collective behavior that is performed by the components that participate in an application collaboration. This may, for example, include the communication pattern between these components. An application interaction can also specify the externally visible behavior needed to realize an application service. The details of the interaction between the application components involved in an application interaction can be expressed during the detailed application design using, for example, a UML interaction diagram.

An application collaboration may be assigned to an application interaction. An application interaction may realize an application service. Application services and technology services may serve an application interaction. An application interaction may access data objects. The name of an application interaction should clearly identify a series of application behaviors; e.g., “Client profile creation” or “Update customer records”.

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An application function represents automated behavior that can be performed by an application component.

An application function describes the internal behavior of an application component. If this behavior is exposed externally, this is done through one or more services. An application function abstracts from the way it is implemented. Only the necessary behavior is specified.

An application function may realize one or more application services. Application services of other application functions and technology services may serve an application function. An application function may access data objects. An application component may be assigned to an application function (which means that the application component performs the application function). The name of an application function should preferably be a verb ending with “ing”; e.g., “accounting”.

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An application collaboration represents an aggregate of two or more application components that work together to perform collective application behavior.

An application collaboration specifies which components cooperate to perform some task. The collaborative behavior, including, for example, the communication pattern of these components, is modeled by an application interaction. An application collaboration typically models a logical or temporary collaboration of application components, and does not exist as a separate entity in the enterprise.

Application collaboration is a specialization of component, and aggregates two or more (cooperating) application components. An application collaboration is an active structure element that may be assigned to one or more application interactions or other application internal behavior elements, which model the associated behavior. An application interface may serve an application collaboration, and an application collaboration may be composed of application interfaces. The name of an application collaboration should preferably be a noun.

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