What is mainframe modernization?
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Published: 09 February 2024
Contributors: Mesh Flinders, Ian Smalley

What is mainframe modernization? 

Mainframe modernization is a process enterprises use to migrate their existing legacy systems to a newer, more technologically advanced ecosystem. Some of the most frequently targeted areas for modernization are code, interface, potential cost savings and performance.

Modernization approaches can vary widely in scale and scope, with some taking on a total overhaul of an existing system’s functionality and code base while others target more specific areas for innovation. The second approach is more widely used since underlying technologies are often costly and risky to completely replace. The thinking behind the second, more cautious approach to modernization is that while an underlying technology may have changed since a computer system was installed or an app was created, data migration from one system to another can be risky and expensive.

Choosing the right mainframe modernization solution is critical to keeping your hardware and software up to date and staying competitive in a rapidly changing IT landscape. Since most enterprises use mainframe systems to run their most critical mainframe workloads and store valuable data, business leaders are increasingly prioritizing mainframe modernization and making large investments in the space. According to a recent IBV whitepaper commissioned by IBM, 71% of executives say mainframe applications are central to their business strategy and four out of five executives say their organizations need to rapidly transform to keep up with the competition.

Why do mainframes need to be updated regularly?

Mainframes are computers with large amounts of memory and data processors that perform simple calculations and transactions in real time. Mainframes are critical to the core business processes of many enterprises including commercial databases, transaction servers, and applications that depend on their security and resiliency.

Mainframes that were installed as little as 10 years ago can still pose a considerable risk to an organization on several fronts. First, inefficiencies from older technology can increase operational costs and make businesses vulnerable to newer, more innovative competitors. Second, legacy applications created with old programming languages can pose performance problems and be difficult for younger coders who were trained on modern coding languages to solve

One example of this is in the code languages COBOL (Common Business Oriented Language) and Java—two of the more widely used coding languages for building applications. Despite their popularity, COBOL and Javastill have key differences that need to be considered for a mainframe modernization initiative to be effective. While Java is more intuitive for many programmers because of its similarities to C++, COBOL’s syntax is designed for business-oriented deployments and is considered more readable.

Here's a closer look at how mainframe modernization works and why it’s become such a central part of any of digital transformation initiative.

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Why is mainframe modernization important?

The rise of artificial intelligence (AI), unstable geopolitical situations in Europe and the middle east, COVID-19—the last few years have seen the business world rocked by a seemingly endless chain of disruptions, often linked to new technology. While it remains to be seen how these unprecedented changes will impact IT infrastructure over time, it’s a safe bet that digital innovation and the need for modernization will remain top priorities for business leaders in the near future.

Mainframes are, arguably, the area of IT infrastructure most vulnerable to change in an organization. The lifeblood of applications and data, mainframes are the beating heart of any enterprise in the tech space, so keeping them up-to-date and running smoothly is of utmost importance. For example, DevOps—the software development workflows enterprises rely on to speed the delivery of high-quality software and apps—relies heavily on the effectiveness of mainframe IT systems.

More than perhaps ever before, enterprises see the need to integrate and extend their mainframe capabilities to drive innovation and increase resiliency. Mainframe modernization strategies can help drive digital transformation and capture new value. According to a recent IBV whitepaper commissioned by IBM, 45 of the top 50 banks, four of the top five airlines, seven of the top 10 global retailers, and 67 of the Fortune 100 companies leverage the mainframe as their core platform. 

    Five benefits of mainframe modernization

    Here are five benefits organizations typically realize with a strong mainframe modernization approach.

    Increased pace of innovation

    Legacy mainframe modernization helps enterprises keep pace with new technologies and ensures their competitors won’t gain a technological edge. What’s more, newer technologies are more easily updated than their predecessors, making future upgrades simpler and cheaper.

    Reduced costs

    By itself, installing, operating and maintaining IT infrastructure is one of the biggest costs many enterprises face. Add to that the fact that older tech is more cumbersome and less easily integrated into new applications that your business needs, and it’s easy to see how not upgrading older IT can be less cost-effective in the long run than a mainframe or application modernization initiative.

    More technologically advanced workforce

    Mainframe modernization is an opportunity to add skills and capabilities to your employees, making them more competitive and able to contribute better to your critical operations. For example, if your applications were coded more than a decade ago, chances are your coders could use a refresh as much as their code. An investment in a modernized mainframe isn’t just an investment in your tech assets, but in your people as well.

    Improved automation and productivity

    Upgrading IT systems is a great way for businesses to take advantage of the many automation capabilities that have been introduced in recent years. Automating mundane tasks like scheduling, maintenance and data entry helps employees refocus their time and energy on more value adding activities.

    Deeper insights from your data

    Mainframe data—about customers, workflows, maintenance issues and more—often sits unused for years inside legacy systems. Mainframe modernization solutions that utilize new technologies like artificial intelligence (AI) and machine learning (ML) can help leverage your company’s historical data and spot critical strategic insights.

    What to expect from mainframe modernization

    While there are different approaches and strategies to mainframe modernization, at a fundamental level, they all involve the upgrading of existing IT systems and applications. Scope, scalability and other requirements can vary depending on business need, so it’s important for stakeholders to be in alignment on their expectations for a project, as well as its potential risks.

    Common risks of mainframe modernization

    Any modernization initiative—regardless of scope—comes with certain risks. The complexity of upgrading technology that was installed 10, 20, even 30 years ago is simply too great to eliminate risk entirely. Here are some of the challenges a mainframe modernization project typically faces.  

    1. Skill gaps with existing employees: One of the most frequently cited reasons for not modernizing IT infrastructure is the need overhaul your work force along with the new technology you’re installing to ensure you have skilled workers who can operate and maintain it. Retraining existing employees on new IT systems and/or or hiring new ones who have already been trained on these systems can be expensive and disruptive.
    2. Disruption of normal business processes: You wouldn’t be trying to modernize your mainframe if it wasn’t one of your most critical IT assets. By that same logic, shutting it down—even partially—to make much-needed upgrades can be expensive. Downtimeand service interruptions can create poor customer experiences and cause users to look elsewhere.
    3. Complexity of legacy systems: Systems that were installed a quarter of a century ago typically haven’t been sitting untouched for that long. In most cases, engineers have piece-mealed solutions together using newer tech to stop-gap larger problems without replacing equipment. This can result in a confusing blend of technologies, old and new, that can be difficult for engineers to upgrade without causing a disruption. 
    4. Maintaining compliance and protecting critical data: Data integrity and compliance capabilities are critical to most enterprises, especially ones in the financial services or healthcare industries, where the information they’re charged with safeguarding is highly confidential. Companies undertaking a mainframe modernization initiative are especially vulnerable to cyberattacks and data breaches that can be costly in both financial and reputational terms.
      Secure approaches to mainframe modernization

      While these risks can’t be eliminated altogether, these widely used approaches to mainframe modernization can lower them considerably while still allowing organizations to reach their modernization goals.

      1. Mainframe migration to the cloud: One of the most common and effective mainframe modernization approaches involves moving critical IT systems and applications into a highly adaptive, resilient and flexible hybrid cloud environment. This is known as cloud migration. With cloud computing modernization solutions, rehosting increases agility and flexibility and significantly reduces the costs associated with deployment.
      2. Code optimization: Optimizing old, inefficient code (also known as refactoring) is also a popular mainframe modernizationapproach. It involves the rewriting and restructuring of an existing codebase. Refactoring helps increase responsiveness and efficiency and reduce technical debt, or future expenses created by poor architectural decisions made in the present.
      3. Pre-built solutions: A pre-built, off-the-shelf solution is simply a replacement part (or entire IT system) that’s been purchased to replace an older one. Pre-built solutions are among the simpler options available to businesses who want to modernize their mainframe environment but aren’t yet ready to invest in the resources and risks of a move to the cloud or a code overhaul. In an off-the-shelf solution, older IT systems are simply replaced with something newer and more technologically advanced.  
      4. API modernization: APIs can be used to streamline the integration of older IT with newer, more technologically advanced systems. This approach deploys APIs as a bridge between older IT systems and newer applications that can help increase your capabilities without replacing your existing mainframe.
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