Interactive Sourcing 
The Production Planning (PP) heuristic is equipped with an option for interactive sourcing that allows you to interactively choose the sources of supply for each procurement proposal. This option can be used in the case of interactive planning for external procurement scenarios. While planning a distribution center (DC), you can choose the plant from which to source. The availability of key components and capacity load for the key resources are displayed to aid the planner in the interactive planning process.
The interactive sourcing option is available for the heuristics SAP_PP_001, SAP_PP_002, SAP_PP_003,SAP_PP_004 and SAP_CTP_DLG. This feature is enabled from the heuristic settings.
After the procurement proposals are determined based on the results of net requirement calculation and lot size calculation, you can select the source of supply for each proposal. Based on the sourcing profile maintained in the Product Master at the target location, the availability data (availability, day's supply) for key components and capacity load information (available capacity, utilization) for key resources is displayed. The periodicity for the display of availability data is based on the setting in the interactive sourcing profile. For block-relevant resources, you can display the capacity information aggregated to block intervals.
If a large number of procurement proposals exist, the interactive sourcing can be ignored using a setting for maximum number of proposals. For procurement proposals for which a source of supply has not been selected, the default source-selection logic is applied in the heuristic.
For all orders created using the selected source of supply, there is no check for alternatives. For example, if such an order is late, the heuristic does not determine alternate sources to check whether the requirement can be covered in time.