Essentially the same as a SCP product. The age of the Advanced Planning and Scheduling (APS) product has dawned because computing power has advanced to the stage that we can now economically mathematically model the real world where the supply of components and products is constrained by complex constraints such as supplier capacity, sequences, profiles and relationships.

APS covers various capabilities such as "finite capacity scheduling" or "constraint-based scheduling" at the plant floor level, through advanced long time horizon planning and supply-chain planning and coordination.

There is no precise definition of advanced planning and scheduling, but it is quite intuitive to say that APS systems attempt to resolve the shortcomings of the ERP systems as a planning tool. The APS system applies knowledge and advanced technologies to achieve improved plans that take into account most of the factors and constraints that limit the ability to deliver on time.

APS systems consider material requirements and plant capacity to generate new plans, and some of them create a detailed production schedule that sequence the production optimally, to achieve the organization goals (such as minimum inventory, maximum throughput, etc.) as well as customers' due dates. Jobs are placed in the schedule in several different ways, based upon business practices and customers needs.

Supported scheduling methods include :

• Forward Scheduling

• Backward Scheduling

• Minimum WIP (Work-In-Process Inventory) Scheduling

• Dynamic Constraint-Based Scheduling

• Dispatch - Rule Based Scheduling

Planning versus Scheduling

There is no agreed definition of planning versus scheduling. Many believe that the right and only way to achieve accurate due dates is to perform very detailed scheduling. Others believe that it is much more important to put more effort in the planning process. But most agree that the distinction between planning and scheduling is the tradeoff of time horizon versus the level of detail.

APS systems are able to generate plans and schedules very quickly. These systems can be designed to either look over a long time horizon (a few months) with fewer details or more details over a shorter period (a few weeks). Most people agree that the value of detailed scheduling decreases rapidly after two to three weeks.

AMR defines Advanced Planning as follows:

"Advanced planning is the process of balancing materials and plant resources to best meet customer demand while achieving business goals."

AMR defines Advanced Scheduling as follows:

"Advanced scheduling is the process of precise sequencing of all material and plant resources, at an operation level, over the near term time horizon, (typically less than a month) to best meet customer demand."