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What is mainframe modernization and what are its key benefits?

Modernizing a mainframe can make it work faster, be more reliable, and become more aligned with your current business needs. But it also brings many more benefits.
Row of server computers
Published on
April 7, 2022
Last updated on
March 26, 2024

People believe that the steady rise of distributed systems and cloud computing pushes mainframe solutions into obscurity. That may be right, but those who think mainframe systems would fade away quickly and easily are mistaken. According to Precisely, in 2021, astonishing 67 companies on the Fortune 100 list still use mainframes. Why? 

For example, for the banking and finance industry that deals with vast amounts of bit-sized transactional data, mainframes offer the highest transaction processing speed. They can also process the highest volume of transactions. Even some cloud-based services still depend on overnight mainframe-side batch processing of statements and reports. Moreover, 95% of BMC's 2022 mainframe survey respondents still see mainframe computing as a long-term platform that will grow and attract new workloads. But enterprises that keep mainframes alive and kicking wouldn't be able to depend on these machines without modernizing them or utilizing external solutions delivered by mainframe as a service providers.

Read further to learn what exactly mainframe modernization is and what benefits it brings to organizations. This article also covers basic definitions (like computer mainframe definition), challenges to expect (such as project complexity), and various approaches companies can adopt to modernize their mainframes successfully.

What is a mainframe?

A mainframe computer is a type of large, high-speed computer with a lot of processing power, usually used for large-scale data processing and transaction processing. Mainframes are often also used as servers that can support countless workstations. Such computers are most commonly seen in large organizations that use them to perform business-critical tasks.

What is mainframe modernization?

Experts define mainframe modernization as a process of reworking the organization's mainframe computer in order to improve various aspects of its performance. Similarly, mainframe application modernization happens when an organization decides to modify the software on its mainframe and bring it up to modern standards. Usually, this is done to allow for compatibility between a legacy mainframe app and modern software systems in use.

How is mainframe modernization different from mainframe migration?

Mainframe migration happens when the company decides to stop using its mainframe and begin to utilize cloud computing resources instead. Before they can switch to one of the cloud providers, all data on their mainframe computers have to be migrated to the cloud in a form that is compatible with modern cloud-based software. This process can be split to mainframe application migration and data migration.

How to prepare for a mainframe modernization project?

Before starting the work, it's necessary to look at the big picture because a modernized mainframe should be the center of a well-connected internal ecosystem. Your organization needs to understand where and how resources are allocated to create a seamless computer network that integrates systems across the company. 

Mainframe modernization doesn't always have to be an extreme change. Sometimes, minor improvements to hardware and installing current software will be enough. However, for some companies, such modernization will require developing new applications. Most of the time, organizations start their mainframe modernization efforts by analyzing what's working well currently and building upon that. Modernization is a chance to improve the existing capabilities and add new ones. 

How to modernize a COBOL-based mainframe?

Modernizing mainframes based on COBOL programming language can be achieved by integrating them with cloud computing platforms and modern mobile applications written in new programming languages. Today, COBOL works with many programming languages, including JSON, XML, and Java, to provide the host-based and data processing mode that mobile applications require. COBOL-based mainframes can also be integrated into multiplatform DevOps infrastructures.

Although considered by many a legacy programming language, the amount of COBOL code used in business applications actually grows. Created to process vast amounts of transactions efficiently, advantages of COBOL are still recognized and the programming language is still used by many companies, including government agencies. However, it's true that the market experiences a skill gap, and it takes work to hire a COBOL expert.

What are the key benefits of mainframe modernization?

Modern mainframe systems provide a strong foundation for banking, retail, and logistics enterprises, as well as numerous governmental agencies. Modernizing a mainframe can make it work faster, be more reliable, and become more aligned with your current business needs. But it also brings many more benefits. 

1. Better integration capabilities

Many vital government and financial services applications were written in COBOL, which has since steadily decreased in popularity among programmers, while remaining a common business-oriented language. Such organizations can use APIs to integrate COBOL-based software with modern applications used on current workstations, personal computers, and even mobile devices. In other words, you can keep your legacy setup but still benefit from the lean approaches of modern solutions. 

2. Enabling hybrid infrastructure

Maintaining a mainframe doesn't mean organizations can't use cloud-based platforms. And modernized mainframes are much easier to connect with the cloud to create a hybrid infrastructure that lets you benefit from both solutions. It's important to note that when doing so, data security and cybersecurity overall should be a top priority in your mainframe modernization strategy. 

3. Decrease in costs

Mainframes are quite expensive to maintain. As your workloads increase, the maintenance costs grow as well. The licensing fees for hardware and software can be the main drivers of these increasing costs. By modernizing your mainframe and connecting it with the cloud to create a hybrid infrastructure, you can delegate some workload to easily scalable cloud environments and cut costs by paying only for the computing power you really use. 

Top reasons to modernize your mainframe

Cost of maintenance

The cost of licensing fees, dedicated support, and database tools put massive pressure on organizations' bottom lines, causing them to search for reliable partners to support their modernization projects

Lackluster agility

While the modern approach to legacy modernization and mainframe rehosting usually implements Agile and DevOps models for software development, most legacy products are Waterfall-based. This means that their time-to-market is significantly longer, and every change of requirements is a potential programming marathon.

Skills shortage

As more and more mainframe experts retire, COBOL programmers and mainframe system developers are in significant shortage. Most universities and colleges have dropped mainframe courses from their curricula in the face of growing cloud popularity. Since finding professionals with relevant skills has become challenging, organizations need to modernize their mainframes to preserve their usability.

What is the hybrid approach to modernizing legacy systems? 

Hybrid mainframe modernization addresses all the key challenges mainframes present without removing the benefits of retaining mainframe operations. Below, you'll find three different popular hybrid approaches to modernizing mainframes. 

Mainframe as a Service (MFaaS)

The Mainframe as a Service approach is a situation when the organization turns to the pay-per-use model and uses the provider's mainframe hardware, software licenses, disaster recovery, data center operations, and other features. The MFaaS model offers flexible pricing and reduced downtime risk as hosting and maintaining the mainframe infrastructure is the provider's core business. This approach is advisable when your infrastructure becomes too complex and costly to maintain, and your organization lacks in-house employees with relevant expertise

Managed mainframe services

Managed mainframe services are suitable for organizations that prefer to own their mainframe software and hardware assets but want to avoid addressing the challenge of managing mainframe operations in-house due to the lack of critical resources or high costs. In such a scenario, the vendor's job is to care for your mainframe infrastructure. If you already own a mainframe infrastructure, this model offers access to experts who can modernize your mainframe with the latest technologies. 

The 5R's approach

The third approach is based on the 5Rs: retire, retain, replace, rehost, and reenvision. Organizations that follow this method start by analyzing which of these "Rs" should their legacy systems undergo. While Mainframe as a Service and managed mainframe services are two basic outsourcing options that organizations use without impacting or changing their applications, the 5Rs approach focuses on the customizable mainframe modernization strategy.


Mainframe modernization is necessary for the rapidly changing business landscape of today. However, modernizing mainframe applications demands a strategic approach and should be done in phases to avoid becoming too large of a project. 

Before deciding on your approach, consider your organization's current needs and identify the tools required to meet these requirements. New technologies should be assessed on a case-by-case basis - not considered better by default just because they're new. The modernization process must be tailored to your business so the technology works for you, not vice versa. 

Maxima Consulting has years of experience in modernizing the mainframes of top financial services companies and beyond. Our consultants have the expertise to help you modernize your mainframe legacy solution or run a mainframe migration project. Get in touch with our mainframe experts today

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