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Modernizing Legacy Systems – Everything You Wanted to Know Under One Roof

While technologies keep forging ahead, enterprises need to keep up with the trends at all times. This surely keeps the industry leaders on their toes because their software and systems play a pivotal role in adapting, thriving, and making their business competitive in the market.

User behavior and business norms have gone under transformation and so have business applications. Business leaders who drive innovation in their companies need new technologies to empower them in this transformation. They need fast applications, systems that support connectivity and platforms that bring everything together.

Now the question of the hour is, does your current architecture, software or applications hinder your business performance by not meeting the needs and goals? If yes, then it is time to move to modernizing legacy systems.


What is Legacy System?

If a piece of software cannot be deployed with modern processes or systems, it is referred to as legacy software.

A legacy system is an information management system that is based on outdated technologies but is critical for everyday operations. Legacy systems are housed in monolithic and tightly coupled environs. These systems are functional, but they are a burden to the company financially. They require niche IT skills to operate and there is little room for innovation. It hampers your overall user experience.

Having said that, the legacy system is not always referred to as “old” based on its duration of operation. Sometimes the infrastructure itself might not be able to meet the goals of the businesses.


What is Modernizing Legacy Systems?

Legacy modernization is the process of upgrading the infrastructure and systems to achieve operational efficiencies, overcome technology constraints, deliver customer experience expectations. It is an approach that supports adoption and integration with other systems based on modern technology platforms and executes growth in performance, flexibility, and advancement.

Businesses should know that it is more than just a software update. The following factors are crucial and should be evaluated before modernizing the legacy systems.

  • Legacy Software: The applications that are important for the business and that are part of everyday operations from past few years or decades.
  • Legacy Software Modernization: Updating and replacing dated and inefficient applications, processes or systems – partially or entirely.
  • Re-platforming: Updating the applications from scratch either by self-hosting or cloud based hosting.

Legacy System Modernization Strategies

Businesses usually go with either of these approaches while strategizing modernization:

Revolutionary modernization – It is a process where a complete, inside-out infrastructure transformation is done.

For instance, mergers and acquisitions require this approach where businesses must adapt to the infrastructure of the new entity quickly. When legacy systems start posing as a risk factor to the enterprise, a revolutionary approach is pursued.

The catch with this approach is that without any support from vendors, businesses might face security and compliance issues. There is little scope for new updates.

This approach can cause disruption and hindrance; it is expensive too

Evolutionary modernization – It is a multi-phased, long-term approach where the complete transformation of the framework is done.

In this approach, businesses modernize one workload at a time and slowly, but steadily, complete the process. Doing this not only minimizes the disruptions but also saves costs for the business.

Businesses that have a contract with vendors enjoy the benefits of updating their systems till the end of their contract. Hybrid models permit businesses to connect cloud resources to on-premises environs and support evolutionary legacy transformation.

Factors to Note While Choosing a Legacy System Modernization Method

Before going ahead with evolutionary or revolutionary approach, a detailed evaluation of the following factors should be done.

  • Architecture – Evaluation of architecture elements, performance, and ROI should be done to see where modern technologies can deliver better results.
  • Operations – Decide which new skill sets, training and processes should be considered for streamlining schedule and costs.
  • Workload – Analyze applications, workloads and software and estimate their business value, gravity of the situation and ascertain opportunities to improve.
  • Security – Prepare a strategy to secure the systems before, during and, after modernization to avert loss of data, outages or exposure. Accordingly, businesses must adhere to government and industry compliance regulations in the new environment.
  • Risk – Consider any viable disruption to the business and its associated impact to other processes in the organization against the desired results of the legacy system modernization project. Assess the risk of having the legacy system as it is, including the management of out-of-support systems or those with limited support teams.
  • Financial – Outline how much to spend and how to improve resources to assist current operations and the new ones that will be added to the infrastructure.


Benefits of Modernizing Legacy Systems

  • Operational Productivity: Updated IT systems can deliver better, enhance the performance of infrastructure, gives ample time to market products and, provides better experiences for customers.
  • Reduced costs: Deactivating monolithic apps, data space and physical servers minimizes software, hardware, and licensing costs to a great deal.
  • IT agility: With modernized legacy systems, it becomes easier to adapt the environment to react quickly to any seasonal changes, control data, and integrate systems.
  • Security: Without modernization, businesses can face the risk of security breaches and updates can be tough.
  • Compliance: Legacy systems will not be able to carry on with the processes as regulatory auditing and controls become stricter. Penalties or loss of certification can be evaded with the modernization of systems.
  • Competition: Modernization helps to meet customer needs and offer better customer experience by enhancing innovation and services. It also shortens development and release cycles.

Legacy System Modernization Methods

There are seven methods of modernizing legacy systems. Each one comes with its set of pros and cons. These methods are commonly known as Seven Rs. Let us read them one by one in detail.

  1. Replace – As the name suggests, in this method, the business will completely take out the existing system and replace it with the new system along with new requirements and optimized business processes.

    IT teams must plan diligently on how the existing data will be migrated and supported in the new system without hampering the ongoing business processes.

  2. Rebuild – Rebuilding the entire system is the longest and the costliest method of modernization but this is the best approach to gain optimum results. This is ideal for very big businesses who are in a hurry to revamp quickly.

    With this method, the system is rebuilt entirely, legacy systems are fully upgraded to cloud-native environment.

    Methodologies like DevOps and technologies like microservices, containerization, service meshes, and declarative APIs are used to gain scalability, enhance performance, and cut operating costs.

  3. Replatform – In this method, application components are ported to a new runtime platform with minimum changes in the code.

    For instance, moving a COBOL-based system from mainframes to a LINUX or Windows environment. Compilers are available to port applications from one platform to another. Hence, there will be no changes made in the code structure or the system’s features and functions.

    Businesses can benefit from the reduced infrastructure costs with minimum efforts and maximum efficiency.

  4. Rehost – In this method, businesses can manage their investment in legacy systems like ERP or databases and benefit from the cloud infrastructure. They can see improved performance and security of the systems.

    Rehosting is commonly known as “lift and shift” method where businesses can host on the cloud faster without the need of refactoring or re-engineering the existing systems. An example of this is moving a SAP system from an on-premises data center to AWS, where the system and applications are moved as is to the cloud.

    This approach doesn’t utilize the benefits of cloud native tools; hence, it is supported by emulators that aid in running the legacy systems in modern environs seamlessly. You might know about COBOL mainframe emulator for Windows.

  5. Refactor & Rearchitect – In this method, changing parts of the legacy components are utilized to optimize the code to increase performance. This is generally seen in hybrid environments. The changes are done only in the backend; hence it does not disrupt other functionalities in the system.

    Businesses can move the database of monolithic applications to the cloud while still running most of the applications onsite. The architecture of the applications is optimized only with code changes.

    This method gives businesses an ample amount of time to think through each application component and decide the best-fit platform to gain efficiency.

  6. Retain – In this method, you might require support of “connectors” or “bridges” to operate simultaneously with other modern elements in the business.

    Liquidation of the company, an upcoming merger or any other consideration are not the strongest reasons to go for modernization of the legacy systems. There must be a long-term plan to ensure that the important functions are competent.

    Think of retention as a temporary measure, it cannot be a long-term plan. Retain the systems that are critical but when they are becoming ineffective with resource-heavy structure, then think of modernization.

  7. Retire – Evaluate the workload and timelines to decide when to retire the applications and move any remaining resources to other systems that are currently working.

    At times this might require redesigning of the processes to bridge the gap in operations from the retired system. One thing guaranteed is that businesses will be optimized for sure without aged systems.


Preparing for Modernizing Legacy Systems

Irrespective of the size of the project, you need to plan the entire process way ahead of bringing in the vendors. If not, it might affect the functioning of the entire businesses and in worst cases, it can halt the functioning of systems for some time. Consider the below-mentioned points while chalking out a plan.

  • Estimate your maturity:

    The fundamental thing to do in application modernization is to assess your level of maturity. In case this is the first time your business is undergoing modernization, then it is at an early stage of maturity. In such scenario, you should focus on easy tasks like:

    • Duplicate applications or multiple cases of the same application. Here, the identical ones are removed, or instances are consolidated by the IT teams and business units.
    • Overlapping applications or programs that are different but handle same operational functions should be assessed.
    • Applications that are not essential. This is a tricky part because at times business units may fail to identify which are not essential applications to the business. So, to overcome this, the respective teams must come together and identify if the application is crucial or not after a thorough assessment.
  • Design the outline:
  • Collect information about timelines, budgets, and business goals to decide where modernization can provide the highest ROI. Make sure that along with the IT team, data and security teams should also be included at this stage of the preparation process.

  • Plan the stages of ongoing modernization process:
  • The modernization process should be done in such a way that it touches every part of the IT system and applications. Upgrading should make the system and performance efficient; at the same time, it should be easy to use for the customers as well. Decide on the pace and phases of modernization of legacy systems so that it does not hamper the overall business processes.



You may or may not need to modernize legacy systems today. But you can always assess your processes and performances and check when will be the right time to undergo transformation. Staying competitive and continuing to deliver better results everyday needs a sturdy system. Check with your team about the possibilities.

Partner with experts from the industry to get optimum results. At Embitel, we have completed numerous projects on modernizing legacy systems across industries and geographies successfully.

With the help of the right tools, adequate techniques and area of expertise, we will help your business to modernize legacy applications, transform IT operations and streamline your business processes.

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