Providing, Discovering, and Consuming Services 
This chapter explains what, according to the outside-in approach, is necessary to describe a service and make it available, how a user at the consumer-side finds the service and how this user calls the service in their application. For the latter, this chapter is restricted to the case where the service is to be called using a point-to-point connection.
Prerequisites
The more a service is connected with the overall process of a business process, the more important it is to derive the service outgoing from a corresponding model in the modeling area of the ES Repository. This procedure – integrated in a standardization process (governance) – ensures that the use of the service is documented by the model and that the reuse of services is improved (this is unnecessary from a technical point of view).
Note
A service that has been identified and modeled in this way is called an “Enterprise Service”. Technically, this service is implemented on the basis of Web Service technology. Since this chapter is restricted to the procedures that are technically necessary, the term Web Service will be used rather than the term Enterprise Service.
It is assumed in this chapter that the modeling and optional review process has been completed for the services to be implemented.
For more information, see: Design Objects for Defining the Modeling of Applications
Procedure
The following procedure simplifies those steps necessary for service development. The details depends on each use case and are described elsewhere.
To offer a Web Service, define the service design in the ES Repository and use the proxy generation to be able to implement the service in the application system. Finally, you must publish and classify the service in the Services Registry so that it can later be found and used.
For more information, see: Providing Web Services.
To be able to call a Web Service from your application, you must make it easy to locate by a consumer using the classification.
For more information, see: Discovering Services
To be able to call a Web Service in the application of the consumers point-to-point, you must in turn create design objects for the consumer in the ES Repository and use the proxy generation to be able to implement the call in the consumer application system. In addition to this, you must configure the call so that, for example, security settings are defined.
For more information, see: Consuming Web Services Using Point-to-Point Communication
More Information
It is described in the following developer's guide how you call a service using the Integration Server of SAP NetWeaver Process Integration: