Solving the problem of legacy software

Despite the advancement of technology and the benefits of using modern software, lots of companies still choose not to upgrade their software architecture. Many of them are not aware of the threats this entails and although an upgrade may seem like a big investment at first glance, it will be a beneficial move for network security in the long run.

What is legacy software?

Let’s start with a meaning of legacy software. It’s quite simple: Software which is outdated or obsolete yet still in use. Some examples of legacy software or system are the use of outdated versions of Windows, such as Windows XP for the operation of ATMs, or NASA’s use of 1970s-era technology for their space shuttles.

Why do companies still use it?

Legacy software or systems are still used in software engineering or by companies for various reasons:

Many legacy systems simply work well and are reliable. This is especially true if they are used to perform critical daily operations. Moving to a new system can lead to increased failure rates and risky consequences (not only economical but even related to employees’ safety).
The way data is stored is changing, so moving all the data to a new system can be difficult or even impossible.
Legacy software often does not have exact specifications, which makes it difficult to reproduce all the features on a new system.
Some legacy systems simply require older software and components, such as drivers, that are not included in or not compatible with modern environments.

What are the main legacy problems?

Even considering the above-mentioned factors, an upgrade may be more cost-effective due to the risks involved in using legacy software. Problems that may arise include the following:

Security: Using legacy software can cause additional cybersecurity issues. In particular, outdated security functionalities are incapable of protecting against current threats.
External collaboration and communication: Resisting legacy software modernization can become problematic especially for B2C companies. But even for B2B businesses, it is important that communication with all stakeholders runs smoothly. This proves difficult if two companies work on completely different systems, especially if one of them uses legacy systems.
Cost effectiveness: The use of legacy software by a company has several hidden costs. These include maintaining the systems and finding the right employees who not only have knowledge and expertise of the systems, but also who want to work with legacy software. And this can be a very difficult and sometimes even impossible challenge.
Compatibility with new systems: Over time it becomes more and more difficult and costly to implement changes and ensure a seamlessly working IT landscape.
Maintenance problems: Due to a general lack of understanding of the system and lack of resources, maintenance of legacy software becomes more difficult over time.
Cloud adoption problems: Migrations of IT systems to the cloud are often not straightforward, but this issue becomes worse or even impossible for some legacy software.

Legacy software modernisation

There are several proven strategies to upgrade legacy systems:

Complete transformation/replacement: In this case, the entire system is upgraded to latest technology. This strategy obviously requires a larger, one-off financial outlay. It only makes sense as a last resort. When the old system is built on code containing a large number of bugs, and security and performance are down, then fixing the current system doesn’t make sense. Replacing the whole system is a chance to improve technical parameters and to put the company’s processes in order.
Reconstruction: This method takes more time, but often requires less money. This is because it does not require a one-off investment, and instead can be a year-round strategy for the company. Refactoring is the process of changing old code. However, it does not affect the functionality of the system. The process takes place slowly but systematically, and small pieces of code replace the entire system over a period of time. The big advantage of doing this is that the system is not interrupted for very long, so the company can continue performing its processes as normal.
Rewriting the system: Rewriting the code, unlike its reconstruction, does not require “touching” the old code. It only consists of copying its critical fragments and writing a new system almost from scratch. This process takes time and works well mainly when the code of the old system is not too long. Besides, this is a very special scenario as in most cases, it is more than likely that all the code has to be "touched" to adapt these components to the new solutions.

All systems age and over the years they can end up causing a company more trouble than benefit. However, there is a way to avoid the need for large, one-off investments. With a Software-as-a-Service (SaaS) solution companies receive all the updates, maintenance, and support for the systems, so all the software is always up to date.