Getting real-time access to that information in its native form is becoming more important to companies, with today’s requirement of continuous availability. According to market research firm IDC, the top two application integration challenges today are integrating new technologies with legacy systems and the many disparate systems that need integration. Fully 55 percent of the users IDC surveyed felt that it’s “critical” or “extremely important” to have products and services that support integration today. Moreover, this number is expected to increase to 85 percent by 2004.
So enterprises recognize the importance of sharing information between disparate systems. However, the glass house needs to ensure that the organization’s strategic information is never compromised. The challenge is in giving decision makers and other end users real-time access to important data, while maintaining the security and integrity of legacy systems.
The fundamental problem in accessing mainframe data from a Windows application is that the two environments are based on different architectures and are evolving in different directions. (Figure 1 summarizes the architectural differences.) Understanding this is essential to bridging the gap between the two platforms, because these differences mandate the way data is stored, manipulated, and displayed.
The Windows system is based on the Intel architecture. Microsoft intends to continue evolving the Windows platform and to converge on a shared code base for all environments. Microsoft is deploying Windows everywhere, with the goal of surrounding the glass house and, ultimately, rendering it irrelevant. On top of Windows is .NET, which is less a change to Windows than a change to how code is developed and applications are deployed, installed, and maintained. The .NET framework is key to the future of all Microsoft offerings.
The z/OS system is based on the 40-year-old System/360 architecture. IBM continues to exploit the key features of the System/360 architecture — its robustness, reliability, and scalability. IBM now has an absolute monopoly in the System/390 hardware and Operating System (OS) space. The company has invested substantial energy in developing the WebSphere application platforms and the Java language. It’s safe to assume that the mainframe will continue to be the focal point for strategic applications and data.
Accessing mainframe data from the desktop, and getting it into a usable format, can be cumbersome. Options include:
- Moving to a more modern set of applications (e.g., SAP, PeopleSoft, Siebel) — While promising much, these Enterprise Resource Planning (ERP) systems are expensive, slow to implement, and have a host of hidden costs. Many business processes will have to be redesigned and functionality may be lost.
- Creating a universally accessible data warehouse or data mart — Implementing a data warehouse or data mart is time-consuming; maintaining it is even more expensive and complex.
- Transforming the critical data to a relational data manager with a data-distribution capability — Unfortunately, this is more complicated than it might first appear. While redesigning a legacy database, it’s usually necessary to reengineer existing business processes. Legacy databases with older Relational Database Management Systems (RDBMSes) versions aren’t always compatible with newer versions and tools.
- Using ad hoc processes — These include special COBOL extraction programs, screen scraping, File Transfer Protocol (FTP), Network File System (NFS), or e-mail. Companies often use ad hoc approaches either because they don’t want to — or, for some reason, cannot — commit to a more elegant, effective solution. Unfortunately, these approaches aren’t always timely or complete; they’re also people-intensive, error-prone, and enduring. “Sneaker net” is alive and well in virtually all mainframe enterprises.
As noted, all these approaches have serious limitations. A more effective approach is to provide an integration layer between Windows and the mainframe. Providing such a bridge between the Windows world and the mainframe is difficult anyway. Making that bridge easy-to-use and easy-to-install has proven almost impossible — until recently.
It is now possible to make z/OS look like a Microsoft SQL Server, enabling users to free the z/OS data from its “data jail” and make it quickly, easily available on the desktop. This approach includes: