Systems that host Web services are called provider systems. When you create a Web service, you deploy the service on a provider system as a service definition. You configure the service definition by creating service endpoints. The endpoints hold policies and settings, which enable the consumer applications to communicate with and consume the service definitions. The service definition and the runtime configuration (service endpoints) reside on the same provider system.
The provider systems can be SAP AS Java or AS ABAP systems, or non-SAP systems. To consume Web services on a provider system, a technical administrator has to establish a connection from a consumer system to the provider system. If the provider system requires specific settings to invoke the Web services, such as authentication level, WS-RM settings, or transport settings, the connection must meet all necessary requirements.
The technical administrator establishes the connection to the provider system directly by specifying a physical system in the landscape. To define the specific level of communication settings which the provider system requires, the technical administrator creates a communication profile.
Service definitions that are located on provider systems can be published on the Services Registry (SR). The technical administrator establishes a connection to the SR and thus enables consumers to discover the services. Apart from the SR connection, the technical administrator can establish a connection to a provider system over the Web services Inspection Language (WSIL) document.
Consumer applications and their runtime configuration entities (logical ports) are located on consumer systems. The consumer application comprises a Web service proxy, a client application, and a Service Group. The Service Groups contain references to service definitions, which run on the same provider system.
When you want to consume Web services running on a provider system, you have to have configured consumer applications on consumer systems, which invoke the functionality provided by the services. When you create a consumer application (also called consumer proxy), you deploy it on a consumer system. To be able to consume Web services, a business administrator has to configure the consumer proxies at runtime, providing specific settings which are stored into logical ports. The logical port points to the provider system. Moreover, it points to the service endpoint of the configured service definition.
The business administrator can configure multiple consumer proxies by configuring the Service Group which they refer.
Communication profiles are entities that contain policies with which the communication between the provider and the consumer systems have to comply. The technical administrator knows the policies to a given provider system and specifies a collection of settings such as transport settings, WS-RM settings, and authentication level in the communication profile.
As the connection between the provider and consumer systems uses the policies of a particular communication profile, the service definitions must offer endpoints that comply with the policies defined in that communication profile. Communication profiles are also used to create service endpoints to the service definitions.
When editing a communication profile, the technical administrator creates new versions of it, which differ in their settings. The technical administrator creates new versions of the profiles to avoid the breaking of existing consumers or providers in case the current profile changes. It is possible to have multiple profile versions active at a certain time. We recommend that you deactivate the unused communication profiles if there are no consumers or providers that could be broken.
More information about communication profiles: Configuration of Groups of Web Services
To establish a connection from a consumer to a provider system, the technical administrator has to specify several configuration settings in a system connection. The system connection contains specific information about the provider system in the landscape, such as host name and port number, as well as information about the communication profile, defining the policies for communication with that system, the mechanism for the discovery of Web services on it, and the concrete authentication credentials to access the WSDL or WSIL sources. The technical administrator can create only one connection for every provider system in the landscape.
At a later stage, the business administrator can identify the configured provider systems in the SAP NetWeaver Administrator applications by the system landscape directory ID (SLD ID) provided by the technical administrator.