Microservices vs. SOA, or service oriented architecture, which one should you choose and which is better? What makes microservices different from SOA, or service oriented architecture, is that the services within the microservices architecture are designed in a fine-grained manner and maximize language agnostic APIs like REST communication and enhances addressing a lot of issues related to deployment, fault resistance, and scalability – something that SOA is unable to address. This article will go further into detail of exactly what microservices and SOA are, and how they differ from one another.
Microservices vs. SOA
Service Oriented Architecture (SOA)
SOA is a design of an architectural style that was initially intended for breaking monolithic applications into smaller modules oriented towards business objectives. Essentially, the module range in the sizes from small application services to even large enterprise services and relies on messaging protocols like SOAP and AMQP for communication between services.
On the other hand, microservices consist of independently and loosely coupled services designed around a particular task or business function. Microservices, therefore, contains all the required components to fulfill that particular task.
Are They Similar?
When it comes to the scope of the two, they are essentially similar since both of them are designed to focus on business goals. Also, developers need to undergo a cultural transformation that embraces empowerment of cross-functional development teams and decentralization when they want to use either of the two. Lastly, in case a developer settles on SOA or microservices, then they are at will to choose a different programming language that suits them. This comes in handy when the developer wants to process the best feature for the services specific goals.
How Are They Different?
Although they have similar objectives, the two are different in some ways, and these include:
SOA share a single RDMS database, and as the date grows, the characteristics of the data can be heterogeneous where one size fits all data solution in a no longer ideal. On the other hand, each data utilizes its own data store in microservices architecture giving developers a leeway of choosing storage type that offers the best storage and processing needs of the data being used by the service.
Size and Scope
As opposed to SOA, microservices focus on achieving one function, and this ensures perfect performance of that function. This makes the entire use of microservices simple and easy to comprehend. SOA can, however, be composed of multiple functions with a single database, many interdependencies, and ESB and can be very difficult to understand.
Microservices results in faster communication since it communicates through language agnostic protocols over the network. This consequently results in an increased number of remote calls and high degree fault resistance. SOA, on the other hand, communicates through ESB which results in lower overhead and leads to slow communication.
Coupling and Cohesion
The difference in coupling and cohesion are brought about by size, scope and communication differences. Microservices, therefore, feature very low coupling and high cohesion since they focus on a single business function – the components necessary to handle its function, data storage and messaging are encapsulated in a container and services are therefore independently built tested and deployed. Since SOA services are larger in scope, they have more interdependencies, and data storage and communication are handled outside the services which in turn requires an entire application to be redeployed and be rebuilt.
So, which is better when it comes to microservices vs. SOA? As many developers focus on achieving the same successes that large enterprises like Netflix, Uber, Amazon, and eBay they have focused on using microservices to decouple their monolithic applications. The recent trend on the adoption of microservices over SOA has led to developers increasing their scalability and deployment speed. Although SOA has failed on some of the functions it was intended to curb; developers should focus on certain things like having the necessary skills and aligning the services to business objectives. Primarily, they should consider all the advantages and disadvantages of the two.