Technical Communication

The following types of technical communication are described:

Communication with the System Landscape Directory
Communication with and between the integration tools
Communication with and between the monitoring tools

Communication with the System Landscape Directory

The System Landscape Directory (SLD) maintains a PI system landscape on an abstract level. Nevertheless, it is also accessed by many other PI components.

The SLD contains both configuration data of a PI landscape and information about the software components installed. Both PI tools and messaging components need to read certain information from the SLD and, in addition, support a self-registration feature, which PI components use to introduce themselves to the SLD.

Components and Their Communication with the SLD
Component	Communication with the SLD (Read and Write Access)
Java components (Enterprise Services Repository, Integration Directory, central Advanced Adapter Engine, non-central Advanced Adapter Engines, Java Proxy Runtime)	HTTP connection The purpose is to obtain various system data from the SLD as well as a self-registration in the SLD (write access).
Adapter Engine (Java SE)	Self-registration in the SLD (write access).
ABAP proxy generation	No access

Note Note

Each AS Java has an SLD data supplier configuration, which informs the SLD about the technical settings of the respective AS Java. This function is not PI-specific, but it must be activated to ensure the correct technical system data in the SLD.

End of the note.

Communication with and Between the Integration Tools

The integration tools are the Enterprise Services Repository, the Integration Directory, and the proxy generation tools. These tools enable applications to use PI services in the Advanced Adapter Engine.

You can use the Enterprise Services Repository to define application interfaces and mappings between such interfaces. It is used at design time when the application interfaces are defined.

You can use an interface defined in the Enterprise Services Repository to generate proxies directly in ABAP application systems. The interface data must be read from the Enterprise Services Repository.

Java proxies are generated in the SAP NetWeaver Developer Studio or locally (as .jar files) in the Enterprise Services Repository. They are used to develop Java applications that send or receive XI messages.

In the Integration Directory, the actual PI services of the PI runtime are defined. These are the routing of messages and the mapping of message contents.

Internal Tool Communication

The Enterprise Services Repository, the Integration Directory, and the ABAP proxy generation need to communicate for the exchange of data.

Example Example

When the configurator of an integrated configuration wants to use the input help in order to select an inbound interface, the Integration Directory requires a list of all existing interfaces in the Enterprise Services Repository.

End of the example.

The communication is always executed by the bootstrapping mechanism described above and always uses HTTP connections. First, the exchange profile is read to obtain the connection data for the corresponding tool. For this purpose, the connection data for the target system is read, whereas to log on to the target system, the user of the source tool is read.

Cache Refresh of Messaging Components

The Advanced Adapter Engines (as central messaging components) have to react according to the actual configuration in the Integration Directory and Enterprise Services Repository, whenever changes are activated by these tools. For this purpose, the messaging components use a runtime cache, in which the actual configuration data is present. A cache refresh mechanism is used that updates the runtime cache according to the changes made in the Integration Directory and Enterprise Services Repository.

There are several variants of the cache refresh mechanism depending on the scope of the cache refresh (delta only or entire cache refresh) and on the triggering component (tool or messaging component). The bootstrapping mechanism described above is always used for the communication.

Communication for Monitoring

SAP NetWeaver Administrator

Central component for monitoring a PI landscape is the SAP NetWeaver Administrator.

The table below describes purposes as well as protocols of communications required for monitoring. It also lists the originator of a communication (client) and the responding component (server).

Communication Required for Monitoring Purposes (SAP NetWeaver Administrator (NWA))
Client	Server	Purpose of Request	Protocol
NWA	Advanced Adapter Engines Integration Directory Enterprise Services Repository	Ping, self-test	HTTP(S)
NWA	SLD	Reading the PI landscape	HTTP(S)