Why z/OS?

Digital transformation has become ubiquitous – driving higher data and transaction volumes and accelerating the rate of application changes. Hybrid IT architectures rely on off-premises and on-premises IT resources, producing challenges in capacity, scale, availability, and throughput.

The IBM® z/OS® V2.3 operating system delivers the highly scalable and secure next-generation infrastructure hybrid architectures require. IBM z/OS offers extreme performance, availability, scale, I/O support, and security – on premises, off premises, or provisioned as-a-service – for the trusted, real time reaction to business opportunities.

What’s new

The platform for trusted digital experiences

Solutions for your next generation infrastructure

Hybrid cloud

Transform from an IT cost centre to a value-generating service provider, delivering world-class services on-premises or off-premises.

Cognitive computing

Minimise the cost and complexity of analytics by accessing your enterprise data “in-place” with minimal data duplication or data movement.


Focus on a transparent and consumable approach to enable extensive encryption of data in-flight and at rest

Once more a smooth installation of z/OS’ great new functions with z/OSMF that enables us to continuously provide a stable and state of the art platform for all our customers.

– Swiss Re

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z/OS and Apache Spark metering and capping help control workload resources

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