Connecting an AS Java to a System Landscape
Directory

To use the SLD functionality, this system must be connected to an System Landscape Directory in an SAP NetWeaver 7.0 system. For information about the SLD functionality, refer to the respective documentation of SAP NetWeaver 7.0.
A system landscape consists of a number of hardware and software components that depend on each other with regard to installation, software updates, and demands on interfaces.
The System Landscape Directory of SAP NetWeaver (SLD) serves as a central information repository for your system landscape. More information: System Landscape Directory

Bear in mind that the abbreviation SLD is not intended to define a product, since the System Landscape Directory is part of SAP NetWeaver. This abbreviation is only intended to improve readability.
Each AS Java system has a built-in mechanism for reporting data to the central SLD through SLD Data Suppliers. In addition, other applications that run on the AS Java system can find out where the central SLD is located and use this information to connect. Bear in mind that in special cases, for example, for testing or development, the destination SLD to which other application data is reported may be different from the one to which Java EE data is reported.

When you access the SLD, you will see a page that informs you that the SLD server on your system is running. Depending on your setting it is either connected to a system with an SLD or not. If it is not, you have to connect it as described in the steps bellow.
More information: Setting Up the SLD Data Supplier for Java EE Based Systems
More information: Information About the SLD Data Supplier Service in the SAP NetWeaver Administrator
More information: Configuring the SLD Client