One of the business benefits organizations strive to achieve by implementing a service-oriented architecture (SOA) or in utilizing Web services is the opportunity to reuse business components. Asset reuse is one of the core drivers of the SOA or Web service ROI calculation. Although leveraging the service concept provides an avenue for application consolidation and reuse, these same efficiencies also introduce a distinct level of business risk.

For example, in an architecture where multiple distributed applications provide a business with a specific operation, should a single application fail, the impact of the application downtime is isolated only to a limited set of users. Conversely, the practices of application consolidation and service reuse concentrate operations into fewer applications or perhaps a single point of failure. As seen in the Figure 1, the impact or risk associated with a service's failure increases as more entities or business processes are dependent on that service.

Therefore, if a business entity consolidates its applications and exposes a specific operation as a service and the service fails, the potential enterprise-wide exposure to the service downtime can cause significantly more risk.

Although this article is focused on managing the risks associated with application consolidation and service reuse, there are many other challenges associated with reuse that will not be addressed. Topics such as service definition, service granularity, and service access also challenge the ROI associated with reuse.

In spite of the technical risks involved, reusable components are core to the SOA vision. If the business cannot trust these components, these components cannot be reused. Therefore, in order to fully reap the benefits of SOA and Web services, it is critical that companies find an efficient and robust solution that mitigates risk, increases trust, and ultimately promotes reuse. The solution is a visible, objective, and quantifiable quality process that provides users with the confidence to reuse these services (see Figure 1).

Learning from the Automotive Industry
Other industries have learned how to create visible quality processes in order to instill trust in reused products. The automotive industry is a prime example of this paradigm. Various automakers have spent a significant amount of money branding certification programs with the purpose of instilling trust that their used cars are secure, reliable, and valuable. In fact, there really is no such thing as a used car (or a reused car) in the auto industry. Instead, the auto industry has spent a significant amount of money branding these "reused" assets as "certified pre-owned" cars. A visible and comprehensible quality program has evolved the "used car" into a functional and reliable reusable asset by the consumers who purchase them. The trust and confidence exhibited by used car buyers is a direct result of the visible certification (quality) programs of various auto companies.

Consider, for example, various companies in the automotive industry and their certification programs for pre-owned cars as illustrated in Table 1.

As seen in the table, various automakers utilize visible, objective, and quantifiable metrics to demonstrate that their pre-owned cars (reused assets) are indeed secure, reliable, and valuable. If any of these quality metrics were absent, confidence and trust in the used car would also be absent. In the table for example, the point inspection score provides a necessary quality check for the car, the aspect of special financing provides a monetary reward for purchasing the car, and the warranty provides additional benefits for the car should the quality degrade over time. Each of these visible, objective, and quantifiable metrics increases consumer trust and ultimately promotes reuse.

The key to such certification programs is the visibility with which they are presented, lead by the "certification" seal. Therefore, promoting and instilling trust in reused business components in an SOA model must be approached in the same manner as the certification of pre-owned cars in the auto industry: a visible quality process must be in place in order to trust the reusable assets.

Creating a Visible Quality Process for SOA
Similar to the certification programs of used cars, inspection points of business components must be established, executed, and measured before designing or exploring an SOA project. Such a process must be clearly defined, objective, reliable, and repeatable in order to promote trust in the business components that are to be reused either internally or externally.

When exposing business information and operations either within the enterprise internally, or by sharing data with partners externally, the business must ensure that each part of its system is reliable, and that all of these parts interact flawlessly and securely. Visible quality metrics are necessary to promote internal adoption and reuse, as well as to promote business continuity by providing enough metrics to assure and promote trust with external partners.

Internally, the business must enable itself using these business components. The development organization and business groups must be aware that these business assets are available and valuable. Ultimately, the organization must have trust that the business components they choose to leverage are secure, reliable, and compliant.

Externally, the business must enable its partners to leverage these business assets. With external reuse, the issue of risk compounds because of the mission-critical aspect of these business transactions. A down time of an hour cannot only cost substantial losses in revenue but, more important, can foster the perceived lack of quality and reliability in the company in general. Therefore, trust is especially important when reusing external business components.

At the very minimum, companies should utilize interoperability, unit, scenario, regression, performance, and security penetration testing to provide the necessary inspection points for the business components. As with the certification processes that the automotive industry utilizes, a visible and capable quality process is critical for the success of SOA as well. The lack of visibility and an objectively measurable process can lead to the organization and its partners simply not reusing the business components. This lack of trust, which is reasonable when dealing with mission-critical business processes, will deteriorate the efficiencies that the SOA model promises.

Conclusion
Companies have invested enormous sums of money in building and stabilizing the legacy systems that support vital business components. SOAs offer these companies an efficient and robust way to decrease integration expense, increase business agility, and consolidate applications. SOA offers ubiquitous access to services and the capability to share data with business partners, customers, and information systems with unpa ralleled efficiencies. However, reusing business components via SOA inherently increases risk. Not only is the concept of reuse in jeopardy if internal entities do not trust the publisher of the service, but also external entities can reject leveraging the service if they feel that their business process could be at risk by using the service.

The migration to a service-oriented architecture will not be successful without an implementation plan for a robust and objective quality process. Just as in the evolution from "used cars" to "pre-owned cars," a visible quality process will promote trust, promote adoption, increase application quality, and ultimately reduce business risk.