Definition of a Status Network 
A status network represents the entire processing cycle of a document from the beginning to the end of a phase, for example from the creation of a document to its release. The processing steps can be defined and controlled exactly.
Prerequisites
You must define statuses for each document type in Customizing for Document Management by choosing 
Control data 
Define document types Define document status 
.
Features
The statuses that you set in a relationship to one another as predecessor and successor form the status network.
You can allocate a status type to a status if you want to have greater control. The status type assigns specific features to a status, for example you may only be able to set a status when you create a document for the first time (primary status), or there may be important basic data that you are not allowed to change with a certain status (lock status).
In the following processing situations, the system sets a status automatically:
Processing an original application file
Checking in an original application file
The following graphic shows a status network.
Two possible primary statuses are defined as the initial status: A1 and A2. This means that two different processes are represented at the start of this status network.
Complex predecessor and successor relationships are defined for the statuses in this network. These relationships are checked every time a new status is set.
In the following status network, status IR has statuses WR and WK as previous statuses. This means that status IR can only be set if the current document status is either WR or WK.
Activities
Define the important statuses for the document type that represent the processing statuses.
See: Defining Statuses.
Create one or more predecessors for each status. A maximum of six predecessors is checked. When you set a new status, the system checks whether the current status belongs to the number of predecessors of the new status.