Migrating to Windows from Mainframe, Midrange, UNIX, and Linux
Historically, the primary line-of-business applications were run on mainframe, midrange, and UNIX/RISC platforms. These systems provided the performance, reliability, and serviceability necessary to host these workloads. The perception that only these platforms can run key enterprise applications began to change with the release of Windows 2000. With Windows Server 2003, the deployment of mission-critical workloads to Windows Server accelerated. Now, with the release of Windows Server 2008 R2, the largest, most complex tasks are now handled with improved reliability, scalability, and manageability. Additionally, with the lower cost of ownership, the increased agility and the expansive and growing partner ecosystem, Windows Server 2008 R2 provides value far beyond the capabilities of the aforementioned earlier systems.
The following table describes the primary capabilities of the mainframe systems and maps those features to the Windows platform.
For more information, see Enterprise Abilities for Mission-Critical Needs
Midrange systems generally include IBM System i (such as the iSeries or the AS/400), HP OpenVMS, and HP 3000 systems. As with the mainframe, these systems have origins in the 1970s and have grown with the industry. The drop off of these systems in the last five years reflects their loss of relevance. The following table shows some of the major capabilities of midrange systems and the Windows equivalents.
UNIX systems grew up from departmental systems and graduated to the enterprise. Although not tethered to the RISC platform, RISC and UNIX matured in the same timeframe. The following table shows UNIX offerings and some comparable Windows benefits.
For more information, see Enterprise Abilities for Mission-Critical Needs
LINUX developed in the open-source community. For the hobbyists and early Web adopters, this was the preferred platform. As enterprises considered its use, there was obvious insistence that it must be supported 24x7 as opposed to relying on public forums for mission-critical system support. This level of support from companies such as RedHat can be quite costly. The following table compares some key issues for LINUX and Windows.
For more information, see Compare Windows to Red Hat
