What do you call the procedures by which you take your existing software and information assets and enable them to be used in new business processes? I've heard several phrases used: enterprise modernization, legacy transformation, legacy enablement, legacy modernization, and so on. I suspect you've heard even more permutations of these and perhaps some new ones as well. Of the ones I listed, my favorite is the third, legacy enablement. For some people, though, the word "legacy" has negative connotations, though it really should not.
Legacy software is the software installed yesterday as well as what was put in place fifteen years ago. It is very likely the software running critical business processes. It may have come into the enterprise as a result of a merger or acquisition. When a vendor with little enterprise experience tells you that it needs to be replaced, it is the software that causes you to start laughing hysterically.
Fundamentally, "legacy" means the existing IT assets deployed in the IT infrastructure. This represents a significant amount of the value to businesses. To give an idea of the importance of legacy software, it's been estimated that there are over 200 billion lines of COBOL code in existence, 70 percent of the world's business data is processed by COBOL applications and 30 billion COBOL-based transactions are processed daily. Clearly, these are tremendously valuable assets to leverage.
There are both cost and competitive challenges in maintaining legacy systems. Large deployments can be costly and investment for new or replacement solutions can be expensive as well. This means to attempt to maintain both old and new systems there may be unnecessary duplication and a development staff that has an exceptionally broad range of skills is required.
From a business and competitive perspective we can sum up the requirement in one word: speed. Businesses need to respond rapidly to market opportunities and be first to market. At the same time, businesses need scalable, reliable, and secure production applications. Taken by themselves, neither the old or new technologies may result in a solution that is cost-effective, complete, or flexible enough to provide the qualities of service you need to deliver to customers. There needs a bridge that can incrementally extend existing assets while offering the advantages of new technologies like Web services. Luckily, there is such a bridge and it is called "services oriented architecture" (SOA).
In an SOA world, business tasks are accomplished by executing a series of "services," jobs that have well-defined ways of talking to the services and well-defined ways in which they talk back. The implementation of a service does not matter to a user as long as the service responds in the expected way and offers the quality of service he or she requires. This means that the service must be secure, reliable and fast enough. This makes SOA nearly ideal to use in an IT environment where software and hardware from multiple vendors is deployed, or one in which existing IT assets are mixed with newer applications, integration technologies, or data sources.
There are many business and IT benefits from using SOA for legacy enablement. Foremost on the business side is creating new value from existing assets and systems, typically via new business processes and composite applications (for example, portal applications). SOA can help provide real time access to what were previously batch transactions, thereby increasing the speed and accuracy of making business decisions. Reusing critical business data and applications through SOA can help deliver better customer service, thereby improving retention of those customers.
On the IT side, SOA allows you to take advantage of superb quality of services while repurposing critical processes and data. Furthermore, SOA can help you extend and protect your existing legacy investments and developer skills while helping you achieve greater interoperability with other systems in your enterprise as well as those of customers, partners, and suppliers.
It is possible to get the best of the old and new worlds, to take advantage of technology progress while leveraging your existing assets. When you start doing this, you will be on your way to becoming a business that is more flexible and better able to respond to opportunities to better serve your customers and improve your operations. This is what we mean by being an on demand business, and SOA can make your legacy infrastructure continue to work for you in new and better ways.
About the author
Dr. Bob Sutor is IBM's Director of WebSphere Foundation Software. He is responsible for business and product leadership for the WebSphere Application Server and WebSphere Studio software offerings. Previously, Dr. Sutor was IBM's Director of Web Services Technology, responsible for driving the cross-IBM Web services initiative to continue and advance IBM's leadership in providing Web services solutions, products, and services. Prior to this role, he led the global IBM-wide strategy effort for the development and promotion of key e-business industry open standards including XML and Web services. Dr. Sutor is a frequent keynote speaker on all these topics at conferences around the world and is frequently quoted in the press on both business and technology issues. He was a member of the OASIS Board of Directors and was a participated in various W3C working groups. Before joining the IBM Software Group in 1999, Dr. Sutor was a member of IBM's Research staff for 15 years, where he led advanced technology projects related to Internet and scientific publishing. He received his Ph.D. in mathematics from Princeton University and an undergraduate degree from Harvard College.