Scheduling Constraints and Dependencies in Networks

You can use reduction if the time period within which the activities are to be scheduled is not long enough to process all activities. This allows you to reduce the scheduled duration of internally processed activities.

Reduction only affects the activities for which a reduction strategy has been stored. At the most, the system reduces as far as the level of reduction strategy entered in the network header.

During scheduling, the system determines one reduction level for each activity. For example: The system calculates the earliest dates and determines reduction level 2 for an activity. This reduction level is transferred to the latest dates.

Important: Remember to be careful when using the reduction function as the system does not know whether the duration of an activity can be reduced. It does not carry out plausibility checks or check available capacities.

You can use reduction strategies to control how an activity's lead time can be reduced in levels. You can enter a reduction strategy in each activity.

You can define up to six reduction levels for each reduction strategy. For each reduction level, you can enter the reduction percentage you choose.

Subnetworks (along with activity elements and the option of including standard networks in an existing network) are one way to detail a network in the project flow. You can define subnetworks for subnetworks, until you have achieved the level of detail you require. You can therefore create a subnetwork for the subnetwork for the subnetwork, and so on.

You can also create maintenance orders as subnetworks for a superior network that can be scheduled from SAP PS. Data is exchanged between the network and the subnetwork. The assignment to the WBS, sales order, and possibly the configuration data, is transferred from the header of the superior network. The basic dates of the activity are copied as the basic dates of the header of the subnetwork.

It is also possible to copy the settlement rule, the profit center, and the business area. You can also copy the relationships of the higher-level activity to the subnetwork. The control key of the higher-level activity is changed on the basis of the network type of the higher-level network and of the subnetwork. This determines which tasks are carried out by the higher-level activity (relevance for costing, relevance for scheduling, and so on).

Subnetworks detail activities in the main network. This can be done by manually assigning the subnetwork header to the main activity, or automatically using a milestone function. During the assignment, the control key of the main activity should be changed so that, for example, costs are not calculated twice. This can be set up in Customizing, so that the control key of the main activity changes automatically when a subnetwork is assigned.

As of Release 4.0, scheduling of the overall network for the sales order item can be started in the sales order itself.

This function schedules both the network assigned to the sales order item and all other networks linked to this network via a relationship.

This function updates all items in the sales order that refer to the overall network.

Overall Network Scheduling with Selection Options

As well as overall network scheduling (transaction CN24), which you can use to schedule several networks and subnetworks together, you also have at your disposal the function Overall network scheduling with selection options (transaction CN24N).

You use this function along with suitable selection criteria to specify which networks and subnetworks are to be taken into account as part of overall network scheduling.

A prerequisite for the use of the Overall network scheduling with selection options function is that you have defined suitable levels beforehand in Customizing for the project system and you have assigned network types and number intervals. Note that you can only schedule using two levels.

By using a BAdI for Overall scheduling with selection options, you have other functions at your disposal, such as control of data exchange between activities and assigned subnetworks.

Subnetwork Monitor

You can display additional information on the selected activities and subnetworks on a monitor and jump to the next screen to processing or confirmation of activities.