process key for infosource 2LIS_02_SCL

Hi

Is processkey a standard across a module eg: MM and SD. In the transfer rule, there is a coding to check on process key in 2LIS_02_SCL. eg:

if ( comm_structure-processkey = '002' or

comm_structure-processkey = '012' or

comm_structure-processkey = '022' )

and comm_structure-bwapplnm eq 'MM'

and comm_structure-cppvlc <> 0.

result = comm_structure-cppvlc.

returncode = 0.

else.

returncode = 4.

endif.

I would like to know what is the meaning of these process keys? Are the configure somewhere? Can anyone share with me?

Regards

Kang Ring