Building an Event-Driven SOA: Why Change Data Capture Technology Is a Smart Place to Start

by Herman Wallenburg
September 5, 2007

Regardless of industry or vertical, most organizations have the same objective—to understand their customers’ needs and adapt to changing market dynamics. An organization that can adapt quicker than its competitors can provide better and newer services to its customers and gain a competitive edge. The more rapidly new business processes can be implemented and supported by software services, the greater the advantage. That’s the appeal of a Service-Oriented Architecture (SOA), an approach that promises to help a company become more agile and adaptive through faster development of new software oriented to business processes and reuse of existing software components.

This article describes how organizations with mainframes can use Change Data Capture (CDC), a technology that detects events as they occur in the database, to drive an event-driven SOA. Using CDC can simplify the integration of the mainframe platform in an SOA environment, making all activity performed on the DB2 database by mainframe applications available for event detection. Alternatively, those same mainframe applications can now serve events that occur on other servers within the organization.

In event-driven SOA, the occurrence of an event serves as a trigger to the invocation of a business process and one or more associated services. The advantage of an Event-Driven Architecture (EDA) is that it operates in real-time, improving responsiveness and providing greater visibility into business operations through real-time dashboards rather than static reports. Organizations that adopt an EDA approach to SOA can do more than they ever thought possible. They can:

• Populate dashboards for on-demand analytics and Business Process Management (BPM)
• Stay agile by easily modifying events and services to adapt to change
• Quickly respond to opportunities or risks without affecting existing services and normal operations
• Improve customer relationships by getting a better handle on customers’ preferences and buying habits, anticipating the way they’ll use a product or service, and alerting them to promotions before they even ask
• Combine events and services, modify existing services, or create new ones to optimize revenue.

But moving to an EDA is a process in itself, one that’s time-consuming and presents significant challenges, in particular with respect to the integration of newer technologies with legacy applications.

The starting point for any event processing is in recognizing that an event has occurred. How does one capture the discrete application-layer business events that require immediate servicing? In an environment with legacy applications, this can present a real challenge. As always, the choices are to modify the application to produce the necessary event message or find another way to identify that an event has occurred.