Which ALE services are available and what do they do?

To integrate distributed systems you need more than a communication infrastructure and interfaces. Some additional services are required that are provided by ALE:

Business process harmonization:

Within system overlapping business processes multiple functions running on multiple systems are involved and connected through multiple interfaces. The processes are combinations of functions (sub-processes) running on the single systems.

(Example: A business process for customer order management involves functions in sales, manufacturing, warehouse management, finance, and so on. It is possible that the sales functions are carried out on another system than the manufacturing, the warehouse management or the accounting. Furthermore, some information exchange with the customer, a supplier or a bank may be involved in the process.)

ALE helps to coordinate the whole business process by defining it within a global model. In this model the business rules for the distribution are defined.

Via the model the sub-processes get to know which part of the overall process they have to do themselves and when they have to pass the process over to another system. Through this the whole business process gets harmonized.

Receiver determination:

For distributed business processes a sub-process on one application (client) has to start another sub-process on another application (server). It is important that the new sub-process is started on the right server.

Which server is the right one can not be defined by technical values, it depends on the business content of the process.

(Example: A sales system forwards customer orders to two different production systems. To which system a special sales order is forwarded depends on the entries in the sales order (this may depend, for instance, on the ordered material or on the customer). One sales order may also be split into two or more different orders that may be forwarded to different production systems.)

To notify the client which system is the receiver of the communication (server), ALE uses a distribution model.

From this model the applications get the information about the right server. There are special ALE BAPIs and function modules available for this. The receiver determination makes sure that the information is sent to the right places.

Business object synchronization (semantic synchronization):

If business processes run across distributed systems, they have to share some data to be harmonized.

This is data like business information data, master data or customizing data. If this data is changed in any of the distributed systems, other systems have to be informed about the change. There has to be some kind of subscription of the data.

ALE provides a special service for this data synchronization. This service can detect data changes and distribute the information to those systems that need to know about the change. This service also defines which data is shared.

You can determine which fields of a data object shall be common and which fields may vary locally.

Consistency checks:

For a business process running across two distributed applications there has to be some harmonization of the sub-processes in the single applications.

For making sure that the sub processes are harmonized there are special ALE consistency check tools. These tools help to find and repair inconsistencies. By this it can be ensured that the whole ALE business process works in the right way.

Monitoring:

For the monitoring of distributed processes it is not enough to monitor all activities on the single systems.

The overall business process has to be monitored. The ALE monitoring services provide detailed information about the communication process, the sub-process on the other systems and its results.

Database links are created between the business objects in question on the client and the server. This is especially important for loosely coupled applications with asynchronous links. In this case the server can not give return values back to the client directly so that the ALE monitoring is the only channel for feedback.

Error handling:

Another problem with asynchronous communication is error handling. If an error occurs on the server the calling process on the client may have finished already. So the server can not return the error message to the client.

A special error handling process required. This process is one of the ALE services. It uses workflow functionality to identify the error and to start the required error handling.