Overview of ALE technology
The ALE Module is best used for objects such as batch
objects, that are asynchronous in nature. It uses push technology
that requires that there be a server listening for events. Processes
called registering and installing notify the server what to listen
to and from whom to expect information. Registering involves using
a program identifier to give the SAP Gateway a communication point
with listener threads (servers). Function module definitions within
the server interpret data that is pushed out of SAP by providing
a template for this data.
The ALE Module uses the RFC Server Module for event handling.
The ALE Module uses MQ Series queues for Transaction ID (TID) and
IDocs management. The connector checks for subscriptions when processing
the data from SAP to the connector, resulting in transactions remaining
in SAP until the collaboration is started.
- The integration broker sends a WebSphere Business Integration
Adapter business object for SAP. The business object's
data represents a processing request to the connector. The connector
converts the business object to a table format compatible with the
SAP Intermediate Document (IDoc) format. The connector uses Remote Function
Calls (RFCs) to the ALE interface to pass the IDoc data to the SAP system.
- The connector receives data representing an application event
from SAP in IDoc table format. It converts the data to a WebSphere
Business Integration Adapter business object for SAP before sending
it to the integration broker. The connector uses RFCs to the ALE
Module to receive the data from the ALE interface.
Important:
In releases of the connector prior to version 4.8.2, the
connector used collaborations, business objects, and maps to store
Transaction IDs (TIDs) and their status in the repository, and used
the local file system to store IDoc data. Version 4.8.2 of the connector
replaces the previous management of TIDs and IDoc data with the
use of MQSeries queues.
Note:
Because the ALE Module uses asynchronous communication,
it cannot be used when cross-referencing is required.
