7 Min Read

Big bang or incremental? The definitive answer for mainframe modernization  

Oktober 19, 2023 / Vivek Gupta | Sudhakar Sekar

Short on time? Read the key takeaways:

  • One common pitfall derailing legacy system modernization endeavors is the big-bang approach, a high-risk strategy involving replacing the entire mainframe system all at once.
  • Organizations are increasingly turning to an alternative approach: incremental modernization — a step-by-step, iterative process that gradually updates and improves specific components of your mainframe ecosystem.
  • By breaking down the process into manageable sprints based on priority, organizations can minimize risks, ensure business continuity and gradually introduce system improvements.

Navigating the complexities of legacy system modernization is a high-stakes endeavor that has tripped up many organizations. The allure of the "big-bang approach," aiming for a full system overhaul all at once, has often led to disruptions, budget overruns and unexpected technical issues.

Fortunately, there's a rising trend towards a more pragmatic alternative: incremental modernization. This approach breaks down the journey into smaller, manageable steps, ensuring a smoother transition while minimizing disruptions.

Why incremental modernization triumphs over the big-bang approach

Mainframe systems, intricate webs of interconnected applications, databases and processes, have evolved over many years, sometimes decades. Trying to replace this entire ecosystem all at once is a formidable and risky task. Incremental modernization, growing in prominence, allows for a gradual update and improvement of specific components of the mainframe ecosystem.

Here are compelling reasons for adopting incremental modernization:

Mission-critical systems can't afford downtime.

Mainframe systems are central to many organizations' business operations, facilitating critical functions like transaction processing, customer management and data storage. Any interruption or failure in these systems can have severe consequences, ranging from financial losses to reputational damage.

Even the most meticulous planning can only guarantee a smooth transition if there are no unforeseen technical issues or compatibility problems. Should things go sideways, incremental modernization lessens the impact of “surprises” that could disrupt vital business operations.

Incremental modernizations make it easier to mitigate high-risk upgrades.

With a big-bang approach, simultaneously tackling multiple workstreams increases the complexity, making it challenging to estimate project timelines and budgets accurately. One of the top advantages of incremental modernization is its ability to minimize these limitations. An incremental approach allows organizations to manage their budgets more effectively. Instead of allocating substantial funding upfront, gradual modernization allows for smaller, manageable investments that deliver visible value at each stage.

Incremental modernization also helps with business continuity from a people perspective. By implementing changes incrementally, employees can gradually adapt to modern technologies, processes or systems, minimizing the learning curve and reducing the chances of resistance or employee dissatisfaction.

Incremental modernizations allow for improved prioritization and cost-effectiveness.

The extensive planning needed for a big-bang approach can be overstated. From assessing the impact on various business units to coordinating with stakeholders across departments, the scale of coordination and synchronization necessary for a successful transformation is immense.

A fundamental aspect of incremental modernization is prioritization. Organizations must identify and prioritize the most critical areas or components that require modernization. This could include outdated legacy systems, inefficient processes or technology gaps hindering productivity and business growth. By focusing on these high-priority areas first, organizations can quickly realize tangible benefits and show the value of modernization to stakeholders.

Breaking the transformation process into smaller, manageable workstreams allows organizations to allocate resources more effectively. Organizations can adopt an iterative approach where resources are distributed incrementally based on the progress and outcomes achieved at each stage. This approach ensures better resource use and enables organizations to adapt and course-correct as needed.

A step-by-step approach to incremental modernization success

Incremental modernization offers a practical and effective alternative to the big-bang approach for organizations seeking successful transformation. By breaking down the process into manageable sprints based on priority, organizations can minimize risks, ensure business continuity and gradually introduce system improvements. But how can you get started? Follow these steps:

  1. Identify your problem internally: Before exploring solutions, it's essential to thoroughly understand the pain points and desired outcomes by talking with your product team, client executives, business teams and technical teams.
  2. Plan your modernization phases: With a clear understanding of your problem, plan each phase to determine the most impactful areas for modernization.
  3. Implement your changes while parallel running: Operate two systems simultaneously — the live and the “sandbox” system. This setup allows you to test and validate the effectiveness of modernization efforts, ensuring core operations remain unaffected.
  4. Review what you learned: Closely monitor the impact of the implemented changes and gather insights that will inform future waves of modernization and allow you to fine-tune your approach.
  5. Start the next wave: It’s time to rinse and repeat. Armed with the knowledge gained and lessons learned from the last wave, you can move on to the next phase of modernization.

Move forward with incremental modernization

By embracing incremental modernization, organizations can unlock the benefits of a transformed mainframe ecosystem while minimizing risks, ensuring business continuity and delivering exceptional customer experiences. To embark on your incremental modernization journey, identify your organization's specific challenges and desired outcomes, engage internal stakeholders and leverage external expertise for guidance, if necessary.

Don't let your legacy systems hold you back — embrace the power of incremental modernization for a successful digital future.

Learn how Unisys can help you modernize your mission-critical applications.

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