Legacy systems are typically the mission critical systems that run at the core of an organization's business and, accordingly, the business logic and data embedded within them offer tremendous value. The problem has always been that organizations have found it either difficult or impossible to modernize and reuse these legacy applications. While many approaches have been tried, most leveraged technologies that were proprietary in nature and consequently resulted in integration
efforts that were point-to-point and not reusable.

But things are changing. Today, many organizations are discovering the value of modernizing their legacy systems using the principles and techniques of Service-Oriented Architecture (SOA). Web services and open standards offer the potential to modernize legacy systems in a meaningful way. In addition, a new generation of technology and tools are making legacy modernization projects simpler and faster than ever before.

So after years of frustration and difficulty, why is it worth giving legacy modernization one more attempt using SOA? The reason is that SOA does not merely make legacy modernization easier – it can take legacy modernization, and the reuse of those assets in other systems, to an entirely new level of value for the organization.

The promise of reuse
The promise of asset reuse is undoubtedly one of the main drivers for SOA adoption today. Most IT executives are extremely excited about the possibility of reusing existing applications and data to develop new solutions and applications for business users. And for most organizations, it is their so-called legacy applications that represent the most substantial investment of time, intellectual property and money over the long haul. Finding ways to reuse and leverage these assets can be the key for organizations to streamline business processes, distill and present information in new ways and even retire redundant systems. The combination of legacy modernization and SOA paves the way to this most valuable type of reuse.

Duplication elimination
Duplication of data and business logic within or across departments is a key issue for many companies. Though few IT leaders would admit it publicly, the existence of multiple versions of the same business logic or data within different applications is a foregone conclusion in many organizations. Anyone who has tried to update their name and address information at their local bank – and expected to have to do the procedure only once – has likely experienced the effects of this pervasive problem. There are plenty of reasons for this situation: poor communication, insufficient technology to leverage existing systems and organizational silos are some of the "usual suspects" that encourage duplication. Eliminating this duplication can clearly provide IT organizations with ongoing savings in maintenance and development. Ultimately, this can translate into real benefit to business users, because IT can refocus their efforts on developing new solutions. A combination of legacy modernization and SOA shows the promise of finally tackling this ongoing challenge.