Integration of legacy systems into a modern enterprise SOA (part 3 + 4)

Integration of legacy systems into a modern enterprise SOA - Part 3 and 4

3. Previous attempts

Previous attempts like "point to point", "hub and spoke" or "batch runs" do only meet some of the demands of current architectures. Furthermore there are several drawbacks, which have to be accepted when using those. Often, these methods are only suitable to solve one problem. A wholistic, integrated method would provide an important benefit.

4. Using the SOA method for integration

To adress the previously specified troubles, it is important to identify the required functionality of the old legacy system. The target would be to provide those as services, so that they can be used by other applications. Legacy systems were often treated as a black box. The underlying business logic was ignored by the caller, so that issues like performance, security and maintenance are hard to include into the overall view. The monolithic structure / tight coupling of the legacy components prevents them from being used in a service-oriented architecture respectively its business processes.

In contrast a SOA landscape consists of a mapping of business processes and the corresponding services. Standards allow the general communication and all components should be lousely coupled, so that the advantages of this archicture (e.g. a high grade of reusability) are ensured.

One of the most important advantages of a SOA are its features for legacy enablement. The use and integration of data and logic from legacy systems considering SOA-specific rules, allows a flexible, real-time use of the legacy recources, while keeping and using the advantages, which is offered by a service oriented architecure. By applicating this strategy a big number of assets of the legacy system and the service oriented architecture can be used, to create additional benefit for your enterprise.

Part 5 will follow next week...