It is unknown how much longer an AS/400 system can be maintained
Just like the old mainframes of the past, such as the IBM34 IBM36, the AS/400 is getting old. In fact, IBM encourages business to upgrade their system. However, for many businesses, it makes more sense to migrate their computer data to a Windows server.
You will have more software and hardware options
Once you have a Windows server you will have access to a much greater range of software programs. Along with software, there are more third-party developers of hardware. You will also be able to train your employees more quickly, as familiarity with a Windows based system will be more intuitive than it is for an IBM operating system.
Maintenance costs are lower
It is usually easier to upgrade and install software, including patches, with a Windows server than a traditional mainframe server, and depending upon the size of your system, it is usually easier to have software and computer technicians on your payroll to maintain and troubleshoot the system when there is a problem.
Windows based servers continue to improve their capabilities.
Over time, microprocessors have become faster and more robust. As each new generation is introduced, the mainframe computers lose their advantage over windows servers. There may come a time in the future when IBM simply throws in the towel and moves on to other products and services. They have done this many times in the past. It makes sense to begin planning for a migration to a Windows based server today, so you are not in a rush to do it in the future.
The AS/400 system has been around for many years, and is therefore time tested. The vast majority of people using this system have had a good experience with it, so as long as there is no problem, you can stick with it. In other words, if it's not broken, there is no reason to fix it. Of course, eventually it will need to be replaced. For most companies, a Windows based server will get the job done. All that is needed is a data migration strategy, and this is easily accomplished with software that extracts the data from your current system and formats it for a Windows based server.
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