Distribution of Data using Application Link Enabling 
Using Application Link Enabling, you can distribute budget data between different systems. This means that, in the Budget Control System (BCS), you can send budget information from a sender to a receiver system, which will then post this budget data.
The following restrictions apply to budget data linked via ALE:
Only budget entry documents are taken into account for distribution .
Only posted documents can be distributed (not preposted or held documents).
Only data created through a budgeting transaction (that is, in the initial document created) will be taken into account. If the reference fields are not empty, distribution will not take place.
Only budget documents originating in BCS are distributed. Note that there is no distribution of budget entry documents created by a previous distribution run. This means that a document created in the receiver system cannot be used for distribution to another system.
In order to use ALE distribution for BCS, you must carry out the following IMG activities:
Define Central System in ALE Environment
Under a, the following two IMG activities need to be maintained :
Create Standard ALE Customizing Settings
Here, note that all the objects that are needed in order to use ALE must have been created using the IDoctype FMEDIDOC and message type FMEDMSGTYPE.
Define Derivation Strategy for Distributed Budget Data Creating a derivation strategy enables the distribution of budget data to ALE-linked systems for the source fields FM area, fiscal year, budget category, version and funds center.
Via Application Link Enabling, budget data is transferred between two systems using the IDoc technique.
Note
If you send additional budget lines created in the document of the sender system to a receiver system, these lines will not be deleted.
Furthermore, If a budget document for which data has been distributed is reversed in the sender system, this reversal information is then sent to the receiver system. The inbound processing (receiver side) subsequently reverses the corresponding document.
After setting up your distributed system landscape, carry out the necessary Customizing activities. The ALE setup is then ready for use.