Connection to the Application (Connectivity)
TREX can communicate with the application using it by means of an HTTP connection or an RFC connection:
ABAP application accesses TREX by means of an ABAP client (RFC connection)
As a rule, ABAP applications communicate with the TREX servers through the TREX ABAP client using the RFC/SNC protocol. Communication takes place using an Gateway and an RFC server.
Java application accesses TREX by means of a Java client (HTTP connection)
As a rule, Java applications communicate with the TREX servers by means of the TREX Java client using the HTTP or HTTPS protocol. This communication takes place using a Web server that is enhanced with TREX-specific functions.
Initial TREX Basic Configuration
For the initial connection of TREX to the application using TREX, perform the steps described under TREX Post-Installation Configuration and Connecting TREX with an Application immediately after installation.
You work through these and further configuration steps for connecting to the application using TREX using the functions in the TREX admin tool (standalone).
The following functions are available in the 
Landscape 
Connectivity 
area:
Connectivity window
RFC tab
Current
You administrate and configure the RFC connection here:
Repair History
You can monitor the progress of automatic recovery processes (repairs) for the RFC connection here. Information is displayed about the time taken for the repair (Repair Time), the SAPSID user, the type of RFC server (multi/single threaded), the problem that occurred, and the action/solution taken (Solution (Action)).
HTTP tab
You monitor and configure the TREX Web server here: