Connectivity between SAP and SAP BC

Hi All,
I am trying to establish Connectivity between SAP and SAP BC.I has done the required EDI settings in SAP. While configuring RFC Destination (TCP/IP) in SM59 there is a field with name “PROGRAM ID”. Can somebody please tell us what PROGRAM ID is? What value can I select for this field? Thanks in Advance.

Thanks,
Phani Akella.