IBM mainframe Z16 zSystem

Why Banks Love IBM’s zSystem

IBM’s mainframes aren’t the least expensive solutions in the market unless you take into account the risks they mitigate. Banks tend to be very frugal, yet they overwhelmingly favor IBM’s mainframe solution (at least the large banks do). This is because of a number of things: they are more secure and reliable, and when it comes to transactions, there is nothing that can handle the kind of load and financial risk that a financial institution has.

Particularly considering the recent Silicon Valley Bank failure, financial institutions also have huge compliance requirements, and IBM’s compliance capability is unmatched.

Let’s talk about why financial institutions and other firms that don’t want the excitement of a breach or outage favor IBM’s zSystem.


The x86 platform has come a long way. When it first came out, downtime was measured in hours per week. It has improved over time to an impressive five nines which means downtime measured in under an hour per year. But even back when the x86 platform was young, IBM’s downtime was measured in minutes per year because banks wouldn’t tolerate anything higher. These days, the zSystem has seven 9s of reliability which is single-digit seconds per year.

One of the most interesting IBM stories I heard a few years back was about a company that was doing a remodel and found an IBM system that had been accidentally sealed in a room for years. It was still running and being used. It was so reliable no one realized it was there until the wall was opened up.

When IBM builds these systems, it not only stress-tests them to extremes, but it shoots the processors, which are unique to IBM, with photons so they can better anticipate solar radiation, which can flip bits and cause errors in order to make sure they can identify when that happens and correct the related errors timely.


Financial institutions lose billions due to fraud. IBM leads in AI-based fraud detection and mitigation and receives frequent citations from reference accounts that this alone has saved a company hundreds of millions of dollars. IBM has been serious about security far longer than any other tech company. I can say this because IBM is over a hundred years old and has always taken security seriously.

IBM is the only company that has a Quantum Safe solution anticipating the coming quantum wave of attack platforms that will make most existing data protection solutions obsolete. Part of why IBM is so secure is that it tends to own the whole technology stack. Its systems are IBM outside and inside, which creates deeper knowledge of where potential exploits might reside so they can be addressed in-house rather than asking a technology partner to address them.

Not only is IBM secure, but it also realizes that employees and customers don’t want to jump through a lot of hoops before getting legitimate access to stuff, so it created technologies like Homographic Encryption that allow customers access and the ability to work with data that hasn’t been decrypted.


This is another instance where IBM’s platforms truly stand out. IBM worked with compliance auditors to create a level of system transparency that met their needs with regard to access and analysis. I was an auditor, so I know that if you don’t create and maintain a decent level of trust and transparency during an audit, the auditor will bury you even if you didn’t do anything wrong. Your inability will make you look suspicious, and an inability to show you are in compliance isn’t the same as being compliant. You must prove you are following the rules, and IBM’s approach is to make that effort as easy and seamless as possible.

Wrapping up

I’m ex-IBM and I’ve worked with a lot of banks over the years. What I know is that IBM solutions are often more expensive than the competition, but they are also a bargain in the big scheme. They mitigate higher costs from breaches, outages, and embarrassments. Sometimes I wonder whether people don’t buy them because they don’t value the peace of mind IBM solutions bring. The old saying “nobody gets fired for buying IBM” implied, accurately, I might add, that not buying IBM put your job and career at risk. And given the risks and hostile world we now live in, that saying has never been truer.

Some struggle with priorities and value cost absolutely. I think the smart folks value security, reliability, and compliance more highly because they realize the cost of failure will likely exceed the entire cost of the IBM System by a significant factor. Sometimes the true bargain is the solution that assures your peace of mind.

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