Many factors such as mobility and e-business are worthy causes that encourage today’s ISD (IT System Department) to web enable and open their legacy applications to such technologies. However, these new technologies issuing from the “Cloud revolution”, simply “web-enabling” your application may not be enough…
Open and accessible mainframe applications – the first step
The mainframe has recently celebrated its 50th birthday and, despite challenges from other technologies (such as client/server, web, etc.), it still represents a significant part of IT business’ core: as a matter of fact, the Fortune 500 companies still use it extensively within their IT infrastructure. This success is due to the sturdiness of the platform, its proven capacity to support heavy demand, and a history of development which roots go many years back, even if skills issues are appearing lately.
Nevertheless this architecture, on which companies have invested considerable amounts, doesn’t offer the possibility of universal access because of its inherent technology. Information System Departments are therefore implementing solutions that enable a dialogue between today’s user interfaces (internet browsers, mobiles, web services) and their legacy mainframe applications. Naturally, these solutions will have to optimize historic investments and not be intrusive: access to applications should require little or no adaptation in order to remain within their original ROI.
Obviously, the solutions will have to respect existing security standards and work within the existing production support (version control, administration) as to access mainframe applications from diverse interfaces such as browsers (Internet and/or extranet) mobiles, tablets or other capable terminals. Such an increase in user demand will lead to an expanding user base and will consequently demand an enlarged application support platform.
Thanks to HTML5 and Responsive Design technologies, access to applications will be standardized regardless of the back-end hardware, dynamically adapting the presentation according to the supported terminal features… We are far from the mandatory restrictions of old 3270 protocols!
Connecting mainframe applications and addressing all issues
Although offering universal access to mainframe applications is an important and significant technological advance, we must not forget that it is only one aspect of the solution. Indeed, times when IT systems were exclusively composed of mainframe technologies are over.
Since the emergence of distributed systems and, more recently, Cloud technologies, the information system is now a heterogeneous environment with core applications distributed across diverse systems, albeit the mainframe has maintained its dominant position. The functional components of an application are now divided across different systems, and applications are no longer monolithic entities running on a single platform: they will then have to interface with these distributed functional components regardless of their underlying support platform.
Going beyond the boundaries of mainframe technologies, applications will also have to interface with application services of external systems, such as web services. And here is the problem: the inherent development path between these two worlds is completely different. Integrating these diverse application types is a challenge which will have to be met, any integration solution will have to take that into account.
Enabling solutions have provided access to mainframe applications through the conversion of old data formats (3270, COBOL…) into new ones (HTML, SOAP, JSON, XML). The integration of these new services will only be possible through reverse conversion: from new data formats to the old formats, the only ones supported by legacy applications.
Thanks to a new generation of solutions, mainframe applications will now be naturally integrated in today’s modern IT systems.
A new lease of life for mainframe applications
The advent of these new solutions provides new opportunities for legacy mainframe applications: rather than being confined to a “mainframe only” position, the legacy system will be able to use its central position to build specific interfaces for these new external services. Quite a significant functional evolution for the mainframe, as legacy applications become open and accessible to new developments in the IT world.