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The SOA implemented at Credit Suisse is now firmly established within the enterprise and is considered to be a major success. The main benefits experienced can be summarized as follows:


Reuse of services. The business services are used across applications. Although the average reuse factor is only 1.6 when taking into account all services, some business services are used by up to 12 applications. The low average factor is mainly due to the fact that many services are currently used by a single application. Because services are built as soon as there is a single user, it can take some time before a second user materializes. Reuse is driven by the centralized repository containing the service interfaces and detailed documentations.



More efficient application development. Due mainly to the reuse of services, application development has been accelerated considerably. Usually, when a new application is under development, 75 to 80 percent of the required services are already available in the repository. This improves time-to-market of new solutions dramatically and also offers significant cost savings for the development process.



Increase of collaboration. Another benefit consists of the increased collaboration between the business unit developers and the programmers implementing the core business applications. It was also observed that experienced PL/1 programmers, who had become demotivated over the years, participated actively in the development process.


However, these benefits were not achieved without hard work. For one thing, there was continuous uncertainty regarding the approach taken with the integration architecture. This included, for example, complaints that CORBA was too resource-intensive, too complex, and too slow. This objection was not broad-based, however, and the consistent support from top management overcame it.

There was also a critical stage when the Information Bus threatened to fall victim to its own success. As more users accessed the applications built on top of the CSIB, performance, reliability, and availability became indispensable. Again, having management backing and sufficient budget helped to overcome problems during this critical phase.

It also transpired that the decoupling, which had been achieved for internal integration, did not necessarily suffice for external integration, which posed even more demanding requirements on the degree of decoupling.

Finally, the strict bottom-up approach applied throughout the development of the SOA will probably be complemented by top-down considerations in the future. This included more systematic decisions concerning reuse and more specific targets for service developers. One idea is to reduce the overhead for the development of services that might never be reused. Another aspect is the identification of "missing" services, even if they are not immediately needed by an application.

Credit Suisse stresses four main SOA aspects that were crucial to its success:

Interfaces

Processes

Management commitment

Solid technology

Evidence for the success of the Credit Suisse SOA-based integration architecture is based on the fact that the concepts and methodologies initially developed for the synchronous information bus could be reused one-to-one when introducing the asynchronous event bus. Furthermore, the implementation of the Bulk Integration Infrastructure is also based on the same foundation. This demonstrates that both the concepts and the methodology actually produced the desired results and that they are independent from the underlying technology.


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After more than two years of successfully running its SOA and the associated service infrastructure SBB, Deutsche Post has gained much useful experience, which is summarized in the following practical advices [HBa04]:

If you want to reduce IT complexity through integration, start with the business (logical) view and use an architectural approach.

Focus on services (multiple use of data and functionality), not on data interchange (point-to-point communication).

Don't neglect the integration infrastructure layerthis is much more than just "data transport."

The technical integration infrastructure is characterized by long-term stability, so stay vendor-independent and stick to open standards.

The success of a whole integration project mainly depends on the acceptance of all business-driven service participants. So, don't let the IT professionals drive the effort alone!

Deutsche Post managed to reduce time to market significantly. The realization of new services only takes a few days due to the integrated infrastructure. Using the SBB helps keep implementation projects manageable and lean. These projects can focus on service implementations and do not have to worry about data connectivity. Moreover, the SBB can be maintained and updated without having to modify the services themselves.

As we mentioned, there were also some challenges to overcome when introducing the SOA. In particular, the effort initially needed to convince service providers to take reusability into account in their development process was higher than expected. A mixture of persuasion, subsidies, and coercion was necessary to achieve the desired compliance with the SOA standards.

A particularly visible success story was the adoption of the service "Customer Management" in the call center application, which today provides additional functionality such as registered mail. Before this adoption, all call center contacts were manually recorded by the agents, which led to typos and data duplication. Now call center agents have direct access to customer data by simply typing in the customer identification number.

The SOA and the Service Backbone have proved to be successful at Deutsche Post and are constantly extended by involving current and potential users in the overall process.

According to [HBr03], the following extensions are planned for the next major release (SBB Release 3.0) of the Service Backbone:

Instrumentation and service management

Service call routing with intermediaries

"Users and Rights" as a service participant

Pluggable core architecture

Support of "Process Integration" (phase 1) as a service participant

After the successful introduction of the SOA at Division Mail, a rollout at DHL is now under way. In doing so, Deutsche Post will reuse the basic methodology and the Service Backbone developed already. A special team will be set up at DHL that will be responsible for integration and consolidation. This team will be supported by the IT strategy team at Division Mail. The decision to extend the SOA to DHL is also a sign of the positive perception of the SOA at the level of Deutsche Post's top management.

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Из наших - я слышал об Альфа-Банке


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