Decomposition Techniques in Distributed Service Architecture

In this modern era of cloud computing, distributed service design in web applications is quintessential to harness the benefits of scalability and elasticity. Such design can be achieved either by implementing the service-oriented architecture (SOA) or a fine-grained micro service architecture (MSA). Defining the boundaries of the services and decomposing them into separate units is a challenging task in the web service design. Single responsibility principle (SRP) and common closure principle (CCP) are the 2 major guiding principles which drive the decomposition of the backend into micro services. Services can be logically segregated either by (i) delineating the sub-domains of the business served and converting each subdomain into a bunch of services grouped together as a microservice, or (ii) by laying out the major entity model and then building the services related to the capabilities of each entity grouped together as a microservice. Both these approaches have their own benefits and issues. This paper discusses these approaches by taking the real-world examples and explains which pattern is suitable under which circumstances.