Paradigm Shift From Monolithic to Microservices

Microservices have been making waves among forward-thinking application development organizations. In the realm of software development, software architecture holds paramount importance because it serves as a guiding force to shape the entire life cycle of a software system. Software architecture is a foundation for complex digital components built upon a software system. Within this domain, two prevalent paradigms, monolithic and service-oriented architecture (SOA), stand distinct. While monolithic simplifies development using its integrated structure, SOA reduces complexity through modular services. However, both paradigms suffer severe scalability, development cycle, and flexibility challenges. Subsequently, microservice architecture as a modern paradigm emerges to overcome these challenges. This paper presents an in-depth analysis of the paradigm shift from monolithic to microservice architecture. It begins with exploring the monolithic and SOA conceptual landscape and their pros and cons. After that, we delve into the microservice platform, including its basic architecture and implementation stages. Furthermore, we provide the trend of the paradigm shift that highlights the recent developments in the field and identifies the research challenges associated with it. Thus, the paper brings multiple research dimensions for the researchers and lets the software and application development teams improve resilience and expedite their time to market.

I. Introduction

Application development, especially in the Internet of Things (IoT) era [1]–[3], is essential for businesses to meet their diverse operational requirements efficiently. Consequently, the journey of application development started with a monolithic architecture. Later, the journey covers the service-oriented architecture (SOA) era and finally reaches microser-vice architecture since 2014 [4]. Monolithic architecture is a single unit created for the entire project and then deployed to the user computers. Small and medium-sized businesses that deploy their application (Apps) include small e-commerce websites, content management systems, calculators, simple games, etc. Many large-scale organizations like Netflix and Amazon have started their industries with monolith frame-works despite multiple limitations; many applications now use this architecture [5]. Application development with SOA was introduced in 1998 to overcome the monolithic challenges by splitting an application into small services. Companies like IBM, Cisco, and SAP initially preferred this framework. However, its prominence declined due to the communication pattern handled by the enterprise service bus (ESB) [6]. The decline of SOA and rise of popularity in microservices is illustrated through the graph in Figure 1.