Despite the riptides of technical change, mainframe computers have persisted, remaining relevant and indeed indispensable for many organizations. Still, there’s nearly universal agreement that some kind of technical fixes are in order to make mainframe computing more flexible, cost effective, and relevant to the rest of the infrastucture in the years ahead.
Gartner analyst Dale Vecchio has been a frequent commentator on the mainframe modernization topic and in two recent Research Notes painted the options: either migrate, or leverage the mainframe platform to best advantage – perhaps with the help of SOA. In his paper, ''Mainframe Modernization: When the Platform Is the Solution,'' he observed that organizations can expose existing mainframe applications as services.” But don’t expect that to be simple or easy.
Vecchio warns that compromises may have to be made and the services approach will require changes in organizational thinking. “...Organizations should evaluate the impact of this approach on the organization structure, development approach, application infrastructure and operational environment,” he concludes.
Vecchio reminds that getting services from existing mainframe transactions “will require the composition of potentially multiple transactions or data sources.” Connecting the dots between and among transactions he calls "microflows," and that task can present challenges.
“When existing screen-based transactions are combined with other screen-based or callable transactions, the navigation among these various transactions can handle the traditional menu flows of screens and extract data from one transaction to use in another,” he writes. The output of this process can then respond to a service request.
While agreeing that SOA can be a component in mainframe modernizations, Phil Murphy, an analyst at Forrester Research, takes pains to point out that this isn’t necessarily all “new.” Historically, “when monolithic architectures and green screens were all we had,” programmers were writing things that accomplished business function and, in fact, “the statements in that well structured CICS probably have more affinity with SOA than many of the later ‘widget-driven’ distributed code,” he says. Furthermore, says Murphy, the idea of reusable code components was not foreign to the mainframe world. “That’s why I reject the premise that SOA is new and no one ever thought of it before,” he says.
Today, Murphy says SOA can be helpful for modernizing a mainframe environment, but if the modernization doesn’t provide a business value that is visible to the business, it won’t get funded. Whether it is database migration or SOA, “Business doesn’t care about trends or how it gets done, they just want value,” he says. And, in terms of mainframe modernization, Murphy says he believes IBM’s zEnterprise, announced over the summer, will be a game changer.
The IBM zEnterprise System combines hardware – an enterprise server – with a platform for large scale data center consolidation, across multiple platforms. In his Forrester Report, “zEnterprise Should Change the Role of the Mainframe in Application Strategy Decisions,” Murphy suggests that zEnterprise could open “cloud opportunities,” particularly as additional vendors bring further enrichment to the offering.
“There certainly is a role for SOA in all this...but the idiocy is when someone suggests that Fortune 500 firms should throw away all their applications and build something new,” he adds.