Jan Vermeir 12 Sep, 2017
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Did you know that in 2021, numerous manufacturing machines are still operated by Windows 95’s ancient precursor? Since MS-DOS premiered in 1981 (Ronald Reagan just started serving his first term), you may naturally think – how is that even possible?
The short answer is – legacy systems are not easy to replace.
But First – What Are Legacy Systems, Precisely?
As you definitely know, legacy systems are usually understood as “old” software. And that’s true in most cases, but, interestingly, a legacy system doesn’t always have to be ancient. So much so, that from the perspective of 2021, certain legacy system can even come from… 2020!
Because, briefly speaking, legacy systems are any technology that can no longer be supported or updated automatically. It’s also not available to buy anymore and usually is additionally incompatible with modern, more advanced solutions.
So, Why Are Legacy Systems So Hard to Replace?
Interestingly, it’s rarely due to the cost factor. Quite on the contrary. In the long run, it’s usually more cost-efficient to replace a legacy system than to keep it. After all, since legacy systems are no longer supported, this naturally generates frequent problems and additional expenses.
No, the main reason why many Legacy Systems are still in use are risk factors.
Gartner’s definition sheds some more light on the matter – according to it, apart from being outdated, legacy technologies are also critical to day-to-day operations. So, practically, legacy systems are usually the fundament of a key business pillar in an organization. Changing this fundament naturally bears a risk of the structure coming crashing down, because there’s no guarantee of success.
Sometimes, New Systems Can Be Too Risky
For example, crucial data may get lost. Or, even worse, the new solution may not perform in the desired way (it’s important to remember that especially older legacy systems often lack technical specification, which makes it tricky to recreate them with identical features).
This issue is similar to this UX-related question – would you redesign a SaaS application that is unbelievably un-user-friendly, but at the same time generates a stable, satisfying income? Redesigning it might help and attract even more clients… however, it may also kill the service. And ultimately, even your entire company.
In my eyes, legacy systems are often somewhat like Venice. Everybody knows the city is sinking (and will definitely land underwater at some point), but, for now, building a new, better Venice is just not a viable alternative. The only option is to modernize the city’s fundaments.
And that is also frequently the problem with legacy systems. They need to be kept alive because rebuilding them is (for various reasons) just not the optimal choice.
So, if you’re also struggling with your sinking Venice (I mean, legacy system, of course), luckily there are ways to keep it afloat.
How Can You Keep Your Legacy Systems Operational and Safe?
The answer is – modernize. In the simplest of terms, legacy system modernization aims at updating all (or some) of your IT stack to better support your business goals and processes.
Gartner defines 6 main drivers for modernization, which will help you to identify which areas are optimal to work on. These drivers are:
- from the business perspective: business fit, business value, and agility;
- and from the IT perspective, costs, complexity, or security.
So, for example, it’s probably a good time to modernize when your solution’s safety is compromised, or if the cost of ownership is getting sky-high.
How Does Modernization Work?
Once you select the problem you’d like to solve, there’s a number of modernization options to consider. As for today, the IT industry usually identifies 7 various approaches to modernization.
In our list, we’ll rely on Gartner’s nomenclature.
- Encapsulate. Our first approach is a technique for reusing legacy software components. While leaving the code in its current environment, you can leverage and extend your application’s features by encapsulating its data and functions. That way, they’ll be available as services via an API. Encapsulating is one of the fastest and most economical approaches. It’s a good option if your legacy system has a high business value and is based on a code of good quality. However, it’s important to remember that encapsulating won’t change any present core problems, since it’s main focus is capturing the current interface.
- Rehost. Lowest in cost and risk, rehosting means redeploying your application component to another infrastructure – like the Cloud, but it can also be physical – without modifying its code, features or functions. Yet, it’s important to remember, that due to its nature, rehosting to the Cloud doesn’t offer any Cloud-native features; its main focus is to deliver more data safety and better stability.
- Replatform. This means migrating your legacy system to a new runtime platform with only minimal changes to the code, but with no changes to the code structure, features or functions. Compared to rehosting, replatforming delivers some basic Cloud infrastructure benefits.
- Refactor. Refactoring is the most obvious approach to modernization. Its goal is to restructure and optimize the existing code to remove technical debt and improve nonfunctional attributes. Importantly, re-coding an existing application enables embracing the full range of Cloud-native features.
- Rearchitect. With this approach, the goal is to shift to a new application architecture while altering the code to exploit the new and better capabilities of the platform to a full extend. However, it’s important to remember that although rearchitecting is not expensive or risky, it also delivers only mediocre results.
- Rebuild. Rebuilding means redesigning or rewriting an application component from scratch while preserving its scope and specifications. With that approach, you’ll be able to introduce new features, and also take advantage of modern technology.
- Replace. The most drastic measure of all. Sometimes various components need to be moved to the bin and simply replaced because no other modernization approach seems sensible. Obviously, replacing enables you to shape components the way you want to. But if you start replacing too many components, it’s hard to view the process as modernization. In that case, you should consider the risks that made you modernize in the first place instead of building an entirely new solution.
A Step Into The Future
Finally, it’s worth mentioning that modernization is not trivial. It’s usually complex and takes much time. However, for many organizations that can’t simply replace their legacy systems, this is the only way to face the future with their old (but now capable) MS-DOS!
Modernize With us
Interested to learn how we can help modernize your legacy systems? Book a free consultation with our expert!
And if you’re looking to empower your legacy systems with the Cloud, download this e-book for more valuable insights:
Additional sources: https://www.altexsoft.com/whitepapers/legacy-system-modernization-how-to-transform-the-enterprise-for-digital-future/ https://freeportmetrics.com/blog/what-is-a-legacy-system-and-why-do-companies-keep-using-them/ https://rtslabs.com/legacy-system-modernization-your-101-guide/
