Horizons and time fences

Horizons

Generally, a horizon is a time period during which a particular function or planning concept is available. A horizon can either start at the current date, or start at a future date. A horizon in Enterprise Planning is defined by a figure that indicates a number of workdays. This figure represents either the start or the end of the horizon.

Time fences

Generally, a time fence is a point in time before which a certain restriction applies. A time fence in Enterprise Planning is defined by a figure that indicates a number of workdays.

Major horizons and time fences

The most general horizon in Enterprise Planning is the planning horizon. The planning horizon represents the period during which requirements are generated and supply is planned.

The planning horizon consists of an order horizon and/or a master-planning horizon. This yields three possible planning situations:

• Order horizon only
• Order horizon (for shorter-term planning) and master-planning horizon (for longer-term planning)
• Master-planning horizon only

For the first part of the planning horizon, you can set a time fence to prevent Enterprise Planning from making changes in your near-future supply planning.

Order horizons and planning horizons must comply with a number of rules. LN can check these horizons according to the following types of rules:

• Length rules that are based on cumulative order lead times
• A synchronization rule between order horizons at various BOM levels

Other horizons and time fences

The following horizons and time fences are available for all plan items:

• The ATP/CTP horizon, which determines for which period ATP or CTP must be checked.
• The fixed lead-time horizon, which is used in order planning to determine whether Enterprise Planning must use a fixed order lead time or detailed routing data to plan production orders.

When you maintain an item master plan for an item, you can use the following additional horizons and time fences:

• Forecast time fence (ignore the forecast in near-future planning)
• Forecast horizon (used for forecast-based inventory planning)
• Family CTP horizon (optionally redirect ATP/CTP checks to a higher product-family level)

You can use the signal horizon to indicate for which period you want Enterprise Planning to generate a particular exception message.

Diagram of horizons and time fences

• The planning horizon must be greater than zero.
• The order horizon, time fence, forecast time fence, and CTP horizon must fall within the planning horizon.
• The end of the fixed lead-time horizon coincides with the end of the order horizon.
• The end of the family CTP horizon coincides with the ATP/CTP horizon.