Connecting SAP source system to BI system:

To see the connections in SAP system(between R/3 and BW system)

TCODE: SM59In R/3 system:

Look for B3TCLNT800(BW logical source system name in R/3)

Double click on b3tclnt800

Under bw system enter SM59:

Look for T90CLNT090(R/3 logical source system name in BW)

We can also check the dialog defined for SAP R/3 and BW systems(SAME AS BEFORE). The dialogs are also necessary for the communication between the systems.