Screen-Based Modernization: Challenging the Myths

by Greg Mummah
February 9, 2010

Some IT organizations think screen-based modernization can’t address certain types of business challenges surrounding mainframe line-of-business applications. But your business wants change—and they want it now. What can IT do?

In simple terms, screen-based modernization means reusing a mainframe application’s 3270 user interface to provide new capabilities to the business. These capabilities include leveraging green screens to provide a Web-enabled Graphical User Interface (GUI) and using them as an Application Program Interface (API) to service-enable application business logic so it can be accessed by other applications. If your business is complaining about the usability or lack of desktop and Web integration in the 3270 interface, or your Java or Microsoft .NET development teams are griping they can’t access the business logic on the mainframe, your organization is a potential candidate for screen-based modernization.

Mainframe enterprises adopt a screen-based approach because it’s relatively inexpensive and time-to-market is typically short—both of which are advantages when a business is clamoring for change but IT purchases are closely monitored. So why do some IT organizations reject screen-based modernization?

Myth #1: Screen-based modernization means slapping some pretty colors and command key buttons on 3270 screens and deploying them to a Web browser. Many years ago, one-to-one green screen-to-GUI was the first capability offered by screen-based modernization tools, and that capability remains today. Several emulation packages offer it, too. However, wedging screen-based modernization into this limited set of capabilities is a little like saying the mainframe runs only COBOL. Most screen-based GUI modernization solutions offer some or all of the capabilities shown in Figure 1.



These capabilities aren’t mutually exclusive—IT can usually mix and match, which means you can address multiple challenges with a single GUI modernization solution. For example, suppose the business has a general mandate to make mainframe applications Web-accessible to all employees, and the contact center has additional requirements for workflow improvement and desktop/Web application integration. Using a screen-based modernization solution, IT can create a simple one-to-one dynamic GUI to meet the general business mandate, and then use the same tool to enhance the workflow and integration capabilities in GUIs for mainframe applications used in the contact center.

It might surprise some, but 3270 screens can make great APIs for other applications to leverage. Many mainframe shops have fantastic stores of business logic, and green screens are ready-made human program interfaces to that logic. Just because green screens were originally made for people doesn’t erase their value as APIs.