Planning vs Scheduling

Features	Planning	Scheduling
Time Horizon	Long term horizon over 3 to 6 months	Short term horizon over 15 to 60 days
Constraints	Takes both material and capacity constraints simultaneously. Generates work orders and purchase orders automatically after netting of the existing inventory and WIP.	Takes only capacity constraints. Expects material to be available. Does not generate any work orders or purchase orders. Expects this to be generated by MRP
Allocation	Creates the allocation or pegging between supply and demand. For instance, which procurement order should feed to which work order and which work order should feed to which sales order as shown below: PO à WO-1 à WO-2 à SO. This allocation can have many-to-many relationship with multiple procurement orders feeding to multiple work orders.	Allocation created by planning is used in scheduling to come out with upstream and downstream constraints.
Work Center	Decides which group work center to be loaded whether it should load on primary or alternate work center	Decides within the group work center, which sub-resource needs to be loaded
​Material	Decides if alternate item can be used if primary item is not available and comes out with net requirement.	No material planning happens. Expects this to be done by Planning.
Strategy	Typically works backward based on due date of customer orders. If enough time is not available for material and capacity, then it shifts the customer order till enough time is available to fulfill it.	​Can have multiple strategy of forward and backward. It sequences the work orders such that setup time is reduced.