Rules for Connecting Applications on Application Diagrams

In Application Designer, you can represent communication pathways between applications by connecting them. Applications are connected to each other through endpoints.

For more information, see the following topics:

The following sections contain rules and guidelines for connecting applications:

  • Rules for Connecting Applications

  • Guidelines for Connecting Applications

Rules for Connecting Applications

The following rules apply when connecting applications.

  • Connections are always between a consumer endpoint and a provider endpoint of the same underlying endpoint type, such as a Web service. Icons on endpoints represent their underlying type.

    For example, you can connect a database consumer endpoint to a database provider endpoint. However, you cannot connect the endpoint to a Web service provider endpoint or another database consumer endpoint.

  • In general, you can connect a provider endpoint to multiple consumer endpoints.


    You cannot connect a provider endpoint to more than one consumer endpoint on the same Microsoft Windows or Office application.

  • You can connect a consumer endpoint to only to a single provider endpoint.

  • On ASP.NET applications, connecting Web service endpoints with WSDL binding names and namespaces that do not match generates a warning. However, Application Designer does not prevent you from making the connection if the endpoint types are compatible. For more information, see Overview of ASP.NET Applications on Application Diagrams and How to: Reconnect Web Services on Application Diagrams.

Guidelines for Connecting Applications

The following guidelines exist for connecting applications.

  • You can create connections between existing endpoints, or if an application does not have endpoints, you can add them, if supported by the application type. For more information, see How to: Add Endpoints to Applications.

  • Endpoints define their role in communication as consumers or providers of services. Therefore, the direction in which you draw a connection does not affect the direction of that connection.

  • When an application or endpoint is selected, choosing the Connect command from the Diagram or context menu opens a connection dialog box. In the connection dialog box, you can choose a compatible application and a provider endpoint on that application to complete the connection.

  • You can begin a connection from a provider endpoint by using the Connection tool or the Connect command.


    When connecting from a provider endpoint, you can choose a compatible and unconnected consumer endpoint or create a new consumer endpoint on the target application.

  • Though you cannot draw connections directly between applications using the Connection tool, you can draw a connection between an application and a suitable provider endpoint, starting from either the application or the provider endpoint.

  • If compatible provider and consumer endpoints exist, you can connect them by beginning the connection from either endpoint using the Connection tool or Connect command.


    Beginning a connection from a consumer endpoint restricts you to choosing only compatible provider endpoints. You cannot create new provider endpoints as a result of connecting from a consumer endpoint. For more information, see How to: Add Endpoints to Applications.

  • If a connection has been deleted, you can reconnect the disconnected applications directly between their endpoints.

See Also

Other Resources

Defining Communication Pathways on Application Diagrams