|
A fundamental component used to develop services in this way is the enterprise service bus (ESB), a mechanism for adding or changing services. A good ESB minimizes code writing and enables service changes without requiring intimate knowledge of underlying enterprise systems. The ESB delivers high value to business process owners and IT service developers by helping maintain loosely coupled relationships between service interfaces and applications.
This paper discusses the relationship between ESB, loose coupling, and the effort needed to align IT with business process owners.
It Begins With a Business Information Problem
SOA is an approach to integration, and its most fundamental feature has nothing to do with technology per se. SOA's foremost distinction is its emphasis on specific business problems - the need to determine precisely what service the business requires and to focus all efforts on delivering that service in the way that's most likely to provide flexibility and business agility.
Successful SOA begins with the assumption that business process owners have responsibility and authority for solving business information problems. Loosely coupled services and SOA are based on the concept of ownership: responsibility for defining the business information solution rests with the people closest to the problem (business process owners), and responsibility for implementing it rests with the IT staff that helps them run their business.
To ensure that IT provides the required services, business process owners must communicate service needs and desired results to IT - in business language. IT must in turn understand and communicate with business process owners in business terms, using business data.
This is a much different approach from traditional interactions between IT and business units. Historically, IT was centralized, and designated groups were responsible for specific enterprise systems. To solve business information problems, business process owners had to understand which systems and technical requirements were involved with their service needs. They would then have to lobby IT committees and cross-department IT teams charged solely with security, change management, and compliance issues. This often resulted in time-consuming, costly integration projects that delivered merely adequate results.
Aligning Business Needs With IT Solutions - The Enterprise Service Bus
SOA techniques promise far greater flexibility, better business results, and more cost-effective solutions than earlier approaches to integration. Properly implemented, SOA can deliver tremendous return on investment for business process owners.
But skepticism is understandable: a parade of other acronym-laden approaches, each promising similar results, have fallen short. The key to success lies in loose coupling developed through correct use of ESBs.
Though used frequently, the term ESB is not well-defined. People often don't know whether it refers to a product or an enterprise architecture construct. For our purposes, ESB is not necessarily a specific product or tool - rather, it is a set of capabilities distributed throughout the organization to simplify service delivery and implementations. It includes transformation and intelligent routing, brings nonstandard technologies into a standards-based framework, and manages service composition - the creation of high-level business-oriented services from low-level application-specific transactions. It minimizes code writing and enables service changes without requiring intimate knowledge of all enterprise systems.
Most importantly, ESB provides a business-oriented organizing principle for the publishing and management of services.
The inbound request is part of the implementation of an accounting-owned service. The outbound request is a business-level request for a service from another part of the organization. External organizations are shielded from implementation changes; internal applications are shielded from external change.
Suppose a director in a securities firm, for example, is responsible for assuring the quick and reliable execution of all steps required for security, bond, foreign exchange, money market, and derivative trades. His company is a member of the Society for Worldwide Interbank Financial Telecommunication (SWIFT), so he owns the process of connecting the institution's internal trading desk and settlement systems with the SWIFT network. He knows the steps needed to execute and confirm trades, as well as the specific information used to execute and confirm trades according to the firm's process and compliance policies. He knows to whom he must return confirmations, ensuring a complete process that meets the institution's, clients', and regulators' requirements. And he knows where those pieces of information reside - whether in his domain or in other departments, such as accounting or risk management.
|
