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April 2, 2021 | 13:04


A new era opens for the business with new opportunities. But it is impossible to fulfill the advantages of it without legacy system modernization. This decision to modernize the industry is attributed to the company’s future. 

There are only a few things that became better with age. Nevertheless, software systems for managing your business are not on the list of those things. Legacy systems used to support the processes for decades, and their update is a new step. In the last few years, AI, IoT, cloud systems, database analysis transformed to a new level and became essential for successful business strategies. 

Legacy system trends in 2021. Source

Legacy application modernization is an investment in the business. We already live in a world of new technologies. Twenty years ago, it was impossible to imagine that all people would use smartphones for reading news or searching for information on social media. Today it is already a new reality. For business owners, it means that all technological systems must be updated in time. It is the only way to stay in a market. We use to update our computers and phones every few years, and the software system for managing your business is also required to be updated in time. 

Preparing for the Digital Future

Many industries still use technologies that are already outdated. For example, no one is still using a pager to communicate and exchange information with friends. We already have more sophisticated and modern instruments. Simultaneously, the healthcare system in the US and some other countries still use pagers for medical notification. It is not only a legacy system, but it is also expensive for support. Nevertheless, the medical sphere is still using them, mainly because it is difficult to replace the instruments that handle vital business processes in the whole industry.

The transformation of the legacy system. Source

The Healthcare legacy system is not the one that needs to be replaced. The Government Accountability Office in the US defined ten federal legacy system examples that must be modernized in the nearest future. Some of those systems work for decades already. Departments of Health, Education, and Social security administration have run their software for 45 and 50 years without replacement and modernization. The whole list of federal systems that require modernization consists of more than 65 issues.

Considering the challenges and risks.

For many industries, legacy modernization is a necessary step for future development. According to Flexera research, most products have a five-year life cycle. But probably quite often, the company started to plan the modernization only after a crash. In 2018 the Revenue Service could not process the tax information, as the system could not manage electronically-file tax returns. It happened because of the legacy environment, as some tax systems have worked already for 60 years. You never know when the system will fail and contribute to the computer glitch. Moreover, in some cases, it can be challenging to fix it quickly. 

How to choose a legacy system modernisation approach. Source

The next challenge for the legacy digital system is security issues. Hackers usually use the latest generation of software to break the system or steal private data. Old technologies are more vulnerable to hackers’ attacks. 

Legacy computer systems are less productive than new ones. At the same time, they are not only defined by their age. In some cases, the system does not have appropriate support and update, and it is challenging to integrate the software into other new technology. An inflexible system is the same as an old system and often becomes a boundary for software transformation. 

Estimating system modernization costs

Many companies do not realize the actual savings they can have in modernizing old technology. They are sure that the expensive software will work for decades without any other investments. Every few years, all the systems need to be modernized. And the covered cost of legacy software can be much bigger than possible spend on updating it.

For example, all the legacy federal systems cost $337 billion a year. It may look like all the modernization will cost much more. But in fact, system replacement saves more money. For example, the Air Force System-1 was recently fully updated. The cost of technical maintenance grew from $28 million a year to 34. At the same time, this modernization makes $35 million saving a year now. 

It is much more expensive to modernize only several parts of the system. There are a few approaches in estimating the cost of legacy application modernization

The first one is a Putnam Model. This methodology is one of the most accessible, as all the company needs for forecasting the cost is the size of the project. Usually, the size is counted by the length of the programming code. Putnam Model allows you to find time and afford what you need to finish the project and see the modernization’s correct cost.

The second is the Constructive Cost Model. This approach was created in the 80s and uses a simple formula to estimate the project’s cost. COCOMO is a K1* (Thousands of lines of code) K2. In this formula, K1 and K2 are the consistent values chosen regarding the team size, their experience, and the system’s complexity. 

Also, developers use Function Point Analysis to estimate the cost of legacy migration. This approach uses available assets to evaluate the project dynamic, manifested in UFPs or unadjusted functions points. Many companies worldwide use different factors in applying functions points. This system is classical for estimating the final cost. 

Legacy Software Modernization Best Practices

Legacy futures, in most cases, depend on using all the knowledge on modernization in practice. Let’s point to the best examples of software updates.

Legacy enterprise systems modernization and replacement strategies

The best way to provide an effective modernization of the software is to choose the most efficient strategy for the whole process. Architecture-Driven Modernisation is based on an analytical and design approach and not only on migrating from point to point. This strategy can be effective for companies that use aging software language. With ADM, these companies can save flexibility and independence from the platform. 

Applying legacy software modernisation strategies.Source

SABA strategy is a high-level planning and organizational framework. It can help to solve different legacy system problems and make future analysis easier and automated. 

Reserve Engineering Mode is based on an approach to transform the old system into a new environment. At this strategy, data migration is the last step in the modernization process. 

WMU methodology is based on the customer satisfaction approach. For this strategy, the company needs to collect and analyze a vast data set on customer experience and build a modernization on this issue. 

A DevOps Contribution strategy focuses on speeding the legacy enterprise modernization by applying a new software update with fewer mistakes. 

Choosing the best system update strategy is possible in complex decisions and considering all the natural business features. 

Legacy modernization methods

There are two effective methods for modernization strategy. Both ways include complete structure changes. The first one is a revolutionary method that can be more stressful for the company but quite effective. The second one is evolutionary or more gradual. Those methods have positive and negative characteristics, and the decision to choose one of them for the legacy modernization must be based on the analytical approach.

The revolutionary method in the legacy system modernization approach is based on changing all the systems. This radical approach sometimes can avoid enormous damages for the company, such as hacking the data or system downtime. This methodology applies to building a new system from the very beginning and deleting the old one. This approach can be used when there is no sense to modernize the system, as it is too old and will not solve business problems after partial modernization and updates. 

The correlation between approach in legacy modernisation and time, cost and agility. Source

The evolutionary methodology is a more progressive, step-by-step process. This approach usually causes minor damage for the company and includes fewer risks. But the other side of this methodology focuses on minor issues but not on a whole project strategy. Evolutionary changes can fix some problems but will not restructure the system. 

Companies usually want to modernize the system software and not change it all at one time. But synchronization of new technology and old systems usually has many problems. It is usually more challenging to protect the privacy of the system and navigate the data. At the same time, both methods are a baseline for the modernization strategy.

Approaches to legacy system modernization

According to IDC research, more than 65% of the companies will transform software in the next few years. Companies are also planning to increase the investment into modernization. The effectiveness of the assets in many cases will depend on the software modernization approach. 

The migration and Enhancement approach is based on evolutionary methodology. It is one of the most popular techniques that offer system migration and some minor improvement. It is usually based on UX/UI updates and database migration. This method’s limitations are based on the strategy approach, as in this case, the business strategy will be the same, and the replacement will regrade only some technical aspects. 

Legacy system migration to the web. Source

The following evolutionary approach is Correction and Grow, which is usually applied to the modernization of some issues, but not all the product. It can be some code improvements or UX/UI replacements. When the project is updated with this correctness, it became possible to add new functions or structures. 

And the final and the most revolutionary method is Compleat Software Reengineering. For this approach, you need to delineate your software’s functions that you still need and some functions you do not use. According to this design, the software engineers will complete a new system with existing data. 

Legacy system modernization techniques

All those methodologies and approaches in modernization have it’s specific techniques. Let’s briefly point out the most common uses. 

  • Encapsulation allows us to use old software elements. With this technique, you can have access to the layers via API. But the code is left in the current environment.
  • Rehosting is based on transferring a mainframe application to other virtual or cloud infrastructure.
  • Code refactoring is used for code optimization without changing its behavior. This technology helps to improve the structure and solve some technical problems.
  • Replacing the part of the app or the whole system with new instruments. Sometimes it is the best decision to make without complete modernization.
  • Rearchitecting technology allows businesses to apply new software architecture while changing the code. It makes it possible to use all the unique capabilities of the system.
  • Replatform migration is based on modernizing some app versions and code adaptation but using the same functionality.
  • In sum, legacy system modernization is a complex and operose process. It takes much time to choose the best approach and technique for the data migration from legacy systems to new software or adapting some code or functions. In any case, this digitalization process will have a significant influence on the economy and business planning.


    #Digital transformation#Enterprise#Legacy software modernization
    Views: 2080

    Written by:

    Filonenko Vyacheslav

    I've been leading a tech department specializing in eLearning applications and Business Intelligence for 10 years

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