Step-by-step guide to ALE and IDOCs

By Shankar Reddy Chamala, ITChamps Software

Introduction to EDI and ALE: 

EDI (Electronic Document interchange) - EDI is the electronic exchange of business documents between the computer systems of business partners, using a standard format over a communication network.
EDI is also called paperless exchange.

Advantages:

Reduced Data entry errors
Reduced processing time
Availability of data in electronic form
Reduced paperwork
Reduced Cost
Reduced inventories and better planning
Standard means of communications
Better business process

EDI has two process
1. Outbound process
2. Inbound process

Outbound Process:
1.Application document is created.
2. IDOC is generated
3.Idoc is transferred from SAP to Operating system layer
4.Idoc is converted into EDI standards
5.Edi document is transmitted to the business partner
6.The Edi Subsystem report status to SAP

Inbound Process:
1.EDI transmission received
2.EDI document is converted into an IDOC
3.IDOC is transferred to the SAP layer
4.The application document is created
5.The application document can be viewed.

Each IDOC is assigned a unique number for tracking and future reference.

IDOC consists of several segments, and segments contain several fields.

IDOC contains the following three types of records...
1. One Control Record.
2. One or many Data Record
3. One or many Status record. 

In IDOCs the following terms are to be known.
PORT:
Port is used in the outbound process to determine the name of the EDI subsystem program, the directory path where the IDOC file will be created at the operating system level, the IDOC file names and the RFC destinations.

RFC Destination:
Used to define the characteristics of communication links to a remote system on which a functions needs to be executed.

Partner Profile:
Partner profile specified the various components used in an outbound process (Partner number, IDOC type, message type, Port, Process code), the mode in which it communicates with the subsystem (batch or immediate) and the person to be notified in case of errors.

Message Control
Used in pricing, account determination, material determination, and output determination. The message control component enables you to encapsulate business rules with out having to write ABAP programs.

TO Process IDOCS the following TCODES will be used.

On both sides:

Logical System Names SALE
Setup RFC destinations SM59
Port Destinations WE21 

In Source system:

Segment Creation WE31

Basic IDOC Type Creation WE30

Message Type Creation WE81

Assign Message Type To Basic IDOC Type WE82

Distribution Model BD64

Writing Report Program SE38
Partner Profile WE20
Message control NACE

Check IDOCs WE02, WE05

In Destination System:

Creating FM SE37

Assign FM to Logical Message WE57

Define I/P method for Inbound FM BD51

Create Process Code WE42

Generate Partner Profile BD64 

IDOC processing in the same instance of R/3 Clients.

For example two clients in the same R/3 instance.

Client 900.

Client 800.  

To transfer the data between two clients the table structures and their data types should be match.  

In this example, Client 900 is Source system, and Client 800 is destination system.

In Client 900 I have created a customized table and inserted some records.

In Client 800 I have created only table.  

Common Steps in Both Clients: 

Creating the Logical System Names and Assigning to Clients:

Go to TCODE SALE.

IMG path IDoc Interface / Application Link Enabling (ALE) -> Basic Settings -> Logical Systems -> Define Logical System  

Click on Display / Change Button  

Click on New Entries  

Specify the Logical System name and description.

Note: Logical System Naming convention is <SID>CLNT<NNN>

Click on Save and Back buttons

Now you will come back to the IMG path screen. Click on Assign Logical System to client.  

Click on Display / Change Button

Click on New Entries

Click on Save and Back.

Click here to continue...