Legacy app modernization is crucial for businesses striving to remain competitive in a technology-driven market. The most popular approaches to integration include Point-to-Point (P2P), Enterprise Service Bus (ESB), Application Programming Interface (API), and Integration Platform as a Service (iPaaS). While upgrading to new systems is a significant undertaking, investing further in outdated software significantly needs to improve an organization's ability to compete effectively.
On the other hand, legacy applications contain mission-critical data like customer or order history repositories, and perform vital functions such as determining mortgage eligibility. While it's common to view these systems as old and obsolete, they may hold unexpected strengths, providing stability and continuity that many organizations rely on.
This article aims to challenge the typical assumptions about legacy systems and explore how they can still serve as valuable assets in today's rapidly shifting technological environment. It will also provide options to evolve these systems, ensuring they remain relevant and aligned with modern business needs.
What is a Legacy System?
A legacy system is often considered a monolithic architecture that resists scalability inheriting the inflexibility of older systems to integrate with emerging technologies seamlessly. Yet, here we are, with many systems still humming on vintage code. Take COBOL, a grandparent in programming languages, over 60 years old but spruced up with a fresh release in 2014, given that it continues to support a significant portion of ATMs and business transactions globally.
Examples of Legacy Systems
Among the examples of legacy systems in operation, NASA's Voyager 1 and Voyager 2 probes stand out as testaments to the enduring utility and inherent challenges of such technology in space exploration. The Voyagers are the sole spacecraft to traverse beyond the heliosphere, venturing into the vast expanse of interstellar space. Remarkably, despite the passage of decades and the leaps in technological advancements, the legacy systems aboard these probes have continued to function without failure. However, they are anticipated to reach the end of their operational lifespan around 2030 due to power constraints.
Each example reflects the challenges of modernizing legacy systems while preserving their core functionality and reliability. Beginning with code decay and software aging that can significantly impair efficiency, reliability, and the overall ability to innovate. Nevertheless, legacy systems still offer immense value and stability. Strategies like digital transformation, DevOps methodology, as well as cloud and SaaS applications, offer practical pathways to breathe new life into these trusted, vintage systems while maintaining the essential features that keep them vital to the organizations they serve.
Keys for Legacy Application Modernization
Legacy app modernization refers to the process of upgrading the existing legacy system without completely abandoning it, focusing on enhancing and updating its capabilities. The goal is to ensure that different software systems, possibly from different eras of technology, work together harmoniously.
So, how can organizations practically implement an API-based strategy to modernize legacy systems and ensure seamless data integration?
Organizations and business managers need to consider that embarking on the journey of legacy systems modernization is not just about updating old software or hardware; it's about transforming the foundational IT infrastructure to meet contemporary needs and future-proofing an organization. According to Gartner there are seven options to make implementation easier, this way selecting the proper technical approach can be achieved with minimal risk.
Encapsulate
An approach that allows the system to integrate legacy systems into a common user experience (UX) platform. This involves leveraging and extending the existing features by making its data and functions accessible as services through an API. Therefore, it effectively addresses the immediate issue of poor user experience, giving a legacy system the facade of modern functionality.
As one of the most straightforward approaches to legacy application modernization, encapsulation involves breaking down the legacy code into manageable segments while preserving most of the original code and all the data. The transformation from a monolithic architecture to one where these independent segments communicate via APIs leads to a system that operates much more efficiently. This minimizes the risk of overhaul, by refreshing the system's operational efficiency, without changing the code completely. Therefore, it could be a great asset for health systems, just as the one described above.
Rehost
A strategic method for migrating extensive legacy applications with the primary goal of achieving high scalability, reduced downtime, and enhanced performance. It consists in moving the legacy system to a new hardware or software environment without making significant changes to the underlying code. Essentially, It can include migrating to the cloud or a virtualized infrastructure, which not only improves performance and scalability but also reduces the cost of maintenance.
The key advantage of this approach is that it facilitates migration with minimal disruption to the application itself, altering only the physical or virtual location where the application resides—be it shared servers, a private cloud, or a public cloud.
By redeploying the application component to other infrastructure—whether physical, virtual, or cloud-based—the core code, features, and functions remain intact. This ensures that the system operates more efficiently in its new environment, providing immediate operational benefits while setting the stage for further modernization efforts in the future. So if you are looking to optimize your legacy systems without altering the core, this would be a perfect fit.
Replatform
A strategic approach to modernizing legacy systems that involves moving the legacy system to a new platform or technology stack, which often necessitates some modifications to ensure compatibility with the new environment. However, these modifications are typically minimal and do not require deep programming skills. Instead, they are changes that can often be managed by a system administrator, such as connecting a web app to a different database.
By opting for replatforming, organizations can enhance their system’s capabilities and address infrastructure limitations without the complexities and risks associated with a full-scale redevelopment. Replatforming is an attractive option for organizations looking to achieve specific short-term goals while minimizing the need for extensive changes to the application's codebase.
Refactor
It involves revisiting and enhancing the internal structure of existing code without altering its external functionality. The goal is to eliminate technical debt and improve code readability, maintainability, and extendibility while ensuring that the component's original features and behavior remain unchanged.
Rearchitect
A transformative approach to legacy application modernization that involves materially altering the application's code to transition it to a new and improved architectural framework. This strategy offers the opportunity to exploit new technologies and capabilities that were previously unattainable with the old architecture.
The process of rearchitecting requires a deep and thorough understanding of both the cloud platform and the legacy application itself. This includes insights into the application’s functionality, data structure, performance requirements, and usage patterns.
Choosing to rearchitect a legacy system often means embracing cutting-edge technologies and increasingly popular frameworks such as microservices. Adopting a microservices architecture offers numerous benefits, including enhanced agility, faster time-to-market, and the ability to integrate more seamlessly with new business partners. Moreover, it simplifies tasks such as designing, debugging, updating, and leveraging third-party codes, making the application more modular and easier to manage.
This method of legacy app modernization is particularly suited to organizations aiming to not just update but truly transform their IT infrastructure to align with current technological trends and business demands. By rearchitecting, companies can ensure their applications are not only compatible with modern standards but are also poised to take full advantage of the latest developments in software architecture.
Rebuild
Redesign or rebuild the application component from scratch, ensuring that its original scope and specifications are preserved. This process involves thoroughly analyzing the current component to understand its functionality, scope, and requirements. During the reconstruction phase, new code is written from the ground up, leveraging modern best practices and technologies while keeping the original specifications intact. Rigorous testing is conducted to ensure that the new component functions correctly and meets all defined requirements.
Replace
Another approach is eliminating and replacing the existing application component with a new solution. This approach is particularly relevant when the existing system can no longer meet the evolving needs of the business or integrate effectively with newer technologies.
Choosing to replace a legacy system offers an opportunity to completely redesign the application from the ground up. This allows to implement entirely new functionalities and take full advantage of modern technologies, architectures, and development practices.
However, this approach is usually the most resource-intensive, both in terms of costs and time. It requires meticulous planning, extensive data migration, and comprehensive testing to ensure that the transition does not disrupt business operations. The replacement strategy also involves a complete overhaul of the application's architecture and design, aiming to deliver the same or enhanced business functionality using contemporary coding techniques and system architectures.
The most challenging aspect of this method is the data transfer to the new system. Utmost care must be taken during this process to prevent data loss, which can occur due to compatibility issues with the new system. Therefore, this approach should be considered only when maintaining the legacy system becomes untenable due to severe constraints such as outdated hardware, scarcity of necessary skills, or other operational inefficiencies.
It's crucial to highlight that these strategies can be understood as two different ways to modernize legacy systems: either completely rewriting the legacy information system from the ground up or opting for a gradual, incremental migration. Opting for the incremental approach tends to render migration projects more manageable and allows for better predictability in terms of both scheduling and budgeting.
The primary challenge, however, resides in defining the most suitable steps for the modernization process; understanding the challenges for legacy application modernization would be step number one.
Technology Trends Critical for Application Modernization Strategies
Application modernization strategies have become a central piece of business, as global data volume grows yearly.
Research shows a projected 61% growth globally by 2025. Given this trend, it's crucial to refine and unify data into a single source to ensure it remains manageable and valuable. In this section, we’ll explore six major technology trends that lead to application modernization strategies.
Point-to-point Integrations
Point-to-point integrations were common, in the early stages of integration technology; involving direct connections between two systems or applications through custom code or an API. This method, where the receiver and sender of data are directly coupled without an intermediary software program, is simple and efficient for small-scale integrations.
However, as the number of integrations grows, point-to-point connections become unmanageable and risky, leading to a complex and tightly coupled architecture. Although this approach is straightforward for integrating a few applications, it is unsuitable for organizations using hundreds of apps to handle large volumes of data. As businesses scale, the increasing complexity and associated risks of point-to-point integrations necessitate a more robust integration strategy.
Cloud ERP (Enterprise Resource Planning)
The need for integration has existed as early as the beginning of the century. In the 2000s, cloud ERP (Enterprise Resource Planning) was introduced, revolutionizing their traditional role of managing finance and core processes. Driven by AI and powerful databases, modern ERP systems have become the central hub for all operational processes across a business. As ERPs have evolved, so too have other business software applications, growing daily in sophistication and numbers. ERP integration is the method by which a company connects its ERP software with other specialized applications and processes across the entire business.
Today’s best ERPs now come equipped with numerous pre-built connectors, APIs, and integration tools. Typically, the prebuilt APIs in a modern cloud ERP are sufficient to manage several applications, but without dedicated integration software, businesses still rely heavily on IT teams to manage custom APIs, mapping, and coding. ERP integration provides departments and teams access to centralized quality data, promoting business process transparency and effectiveness.
Service-Oriented Architecture (SOA)
Service-Oriented Architecture (SOA) is an architectural style that facilitates the modernization of legacy applications by decomposing them into discrete, loosely coupled, and interoperable services. These services are self-contained, reusable components that other applications can access via well-defined interfaces, utilizing standardized Web Service protocols like SOAP and REST. In SOA, there are three main roles: service providers create web services and register them with a service registry or broker, service requesters locate the services they need via the broker, and bind with the service provider to invoke the required functionality.
Enterprise Service Bus (ESB)
An Enterprise Service Bus (ESB) is a critical architectural pattern for modernizing legacy applications, providing a centralized software component that facilitates integration between applications. An ESB is particularly beneficial for organizations looking to streamline their communication, messaging, and integration processes.
The potential of a centralized ESB lies in its ability to standardize and dramatically simplify communication across the enterprise. It offers an inexpensive yet scalable solution for smaller businesses with less complex operational models.
This centralized approach not only simplifies the integration process but also allows a single team of specialists to develop and maintain integrations, significantly enhancing efficiency. By provisioning servers as needed for combined usage, an ESB shares hardware and software costs, providing a scalable centralized solution.
APIs (Application Programming Interfaces)
Over the past decade, APIs (Application Programming Interfaces) and system integration have revolutionized how organizations across various industries deliver services. The primary driver of this transformation has been the shift in customer expectations, demanding better services delivered faster and at lower costs. APIs serve as the basic building blocks for integration, acting as customizable software layers built on top of applications. They dictate how to interact with an application by providing the messaging format, structure, and contents, and they expose data to external third-party applications.
The design of an API is critical for ensuring ease of use without compromising security. By leveraging APIs and system integrations, organizations can simplify and standardize API management, leading to faster and more reliable outcomes. However, API management still requires manual support and does not yet facilitate rapid integration and automation, hybrid data flows, or data synchronization. Additionally, it is not preconfigured for event-based architecture. Despite these challenges, the advancements in APIs and integration technologies have been instrumental in meeting the evolving demands of today's customers.
Integration Platform as a Service (iPaaS)
Integration Platform as a Service (iPaaS) is a software-based cloud platform that integrates different applications used by a company, facilitating the sharing of data between them. This technology addresses the common problem of information fragmentation, which often leads to inefficiencies and errors. Due to its cloud-based nature, iPaaS is a more versatile, scalable, and competitive solution compared to on-premise integration software. iPaaS simplifies the automation of processes, the development and deployment of data flows between applications, and the connection of workflows.
An iPaaS platform is hosted and managed by an iPaaS service provider, who is responsible for managing and governing services such as security, software updates, and hardware management. This platform allows companies to move specific pieces of data between API endpoints, map data between applications even if the data formats are inconsistent, transform data to make it more valuable for other systems, assess and improve data quality, and enforce various API policies, including authentication and authorization. By integrating data consistently from multiple sources and applications, iPaaS enhances the overall efficiency and effectiveness of business operations.
Challenges for Legacy Application Modernization
Integrating modern systems involves potential risks that need meticulous planning and management. Addressing these risks requires a detailed understanding of both the legacy and new systems, as well as a strategic approach to integration that considers all aspects of the organization’s operational, security, and compliance needs. This careful planning ensures that the transition to new systems adds value to the business without disrupting its current operations or compromising data integrity and security.
Some of the most frequent challenges that organizations are facing while modernizing legacy systems are:
- Integration Complexity: Selecting the right modernization tools in the market can be a daunting task. These tools must not only be robust but also align with the unique business requirements and goals of the organization, ensuring smooth interoperability between old and new systems.
- Cost and Time Overruns: Often, the integration of different systems is more complex and time-consuming than anticipated. This can lead to significant delays and unexpected cost increases, straining budgets and potentially jeopardizing the entire project.
- Operational Disruptions: Modernization can lead to system failures or downtimes. Such disruptions can reduce productivity, affect revenue, and damage the organization's reputation, which might take years to rebuild.
- Data Loss Risks: During modernization, there is a risk of data being lost or corrupted, which can lead to incorrect business decisions and severe financial repercussions.
- Security and Compliance Issues: New integrations can introduce vulnerabilities in the system's security. These vulnerabilities expose the business to cyber threats and potential breaches of regulatory compliance standards.
Real world examples of Legacy App Modernization
Let's consider a real-world example from Ohio. The Department of Health in Ohio collects vital data on blood lead, mercury, cadmium, and arsenic levels from clinical laboratories conducting these tests. This critical health data is typically scattered across various systems, such as laboratory information systems and hospital information systems. The process of gathering and consolidating this data is not only time-consuming but also prone to human error. The Journal of the American Medical Informatics Association highlights a poignant fact: "Integrating data from legacy systems remains one of the greatest challenges in healthcare informatics."
In scenarios like these, efficient application integration becomes both time-saving and lifesaving, underlining its paramount importance. Application integration approaches are essential in modernizing IT infrastructure, ensuring that legacy systems can effectively communicate and operate within the contemporary technological environment.
There are many ways to update legacy systems, but given the risks stated in the Ohio example, a robust strategy based on APIs proves particularly effective. API-based integration allows for the abstraction of data and services without modifying the underlying complexity of the system, thereby simplifying the integration process and reducing the potential for error.