What is ALE
ALE ( Application Link Enabling ) is a basic service within SAP Netweaver AS ABAP with which applications send and receive IDocs.
To send and receive IDocs, the ALE subsytem must be configured accordingly. For this purpose you can use transaction SALE that list the necessary step in the correct sequence. you can see the following picture of transaction SALE.
The Following step of ALE Configuration.
1. Define Logical System
To enter the names of the logical systems in the TBDLS table you can click on Logical System -> Define Logical System node in the SALE transaction. that’s transaction code takes you to the table maintenance of TBDLS table, this table is cross client. Typically the logical system of the client is defined with the system ID <SID>CLNT<xxx>.
2. Assign logical system to client.
To assign the logical system to a client, click on Logical System->Assign Logical System to Client node in transaction SALE. You must implement this assignment of a logical system to a client both for the sending and for the receiving client.
3. Define target systems for RFC Calls.
You need to maintain a tRFC destination for receiving system, click on Communication->Create RFC Connections, The SAP System takes you to transaction SM59 in which you can create a new RFC Connection destination for the target system.
The RFC Destination should have the same name as the logical system of the receiver so that the partner profiles can be generated automatically.
Make sure you have account in the Logon & Security tab which you can log on to the target system. You should maintain the tRFC options in menu EDIT->tRFC Options. If there is a communication error during the transfer of the IDoc to the receiving system, ALE automatically schedule a background job that resend the IDoc. In the tRFC options you can specify how often the system tries to establish a connection and how much time is supposed to pass between attempts and you can also disable scheduling of the background job.
4. Maintain the Distribution Model.
In SALE transaction code, select menu Modelling and implementing business process->Maintain Distribution Model and Distribute Views node or you can use transaction code BD64. Create new model view with short text and insert a message type in this model view.
This distribution model allows you to define which BAPI and IDocs will be exchanged between which systems. In this context each system can function as the sender or receiver
5. Generate Partner Profile.
From distribution model you can select the ENVIRONMENT->GENERATE PARTNER PROFILES menu path to generate partner profiles. In this process the system create partner profile for the sending and receiving system.
You can change or check partner profile by selection menu path Environment->Change Partner Profiles. menu from the distribution model. this take you to transaction WE20. You can view that both sending and the receiving system have been entered under the Logical System ( LS ) partner type.
You can maintain outbound options with double click on message type – outbound parameters, In the Outbound Options tab you can choose Transfer IDoc immediately or Collect IDocs before transfer and transfer them as package, you can specify number of IDocs to be collected, Finally the IDoc type is defined in the basic Type Field.
6. Checking the Port
You can use transaction WE21 to check port which has been created during customer distribution model. Expand Transactional RFC.