Microservices vs SOA- Differences and Similarities explained

After people started realizing the drawbacks of monolithic architecture for software development, they started adapting the latest agile practices. These development processes are flexible and provide reliable architecture for building software.

From the haystack of different architectures, we have found two compatible alternatives that are Microservices and SOA (Service-Oriented Architecture). If you are a newbie in this field, both these structures might look similar because they have many common features.

However, as you start learning and implementing them, you will notice their differences easily. In this article on Microservices vs SOA, we will discuss both architectures, along with their similarities and differences.

So, let’s start with the information and understand both approaches in depth.

Microservices- Overview

Microservice architecture is considered an evolution of SOA because its services are finely grained and function independently from each other. Hence, if any microservice fails in the app, there will not be a breakdown in the app, it will continue to function. This is possible because each service has a specific purpose and is made accordingly.

Different microservices can communicate easily using the app programming interfaces, aka, the APIs. These services are organised for a specific domain, and when they are brought together, they form a complex app for that business.

As each service is independent, this architecture can cater to better functionalities than other ways of app building and app deployment.

This functionality gives microservice apps more fault tolerance than other app development methods. Microservices are frequently developed in the cloud and also deployed in it; in many instances, they operate in containers.

Service-Oriented Architecture (SOA)- Overview

Service-oriented architecture came to the picture in the 1990s and now is an important part of the evolution of integration and app development.

Before this approach, monolithic app development was used which required complex and point-to-point integration. When SOA is used in such situations, it can avoid recreating the in-depth integration.

SOA architecture is an enterprise-wide structure for software development of app components. This approach takes advantage of reusable software services or components.

In SOA, each service has data and code integration that executes a particular business functionality; for eg., checking on the credit of a customer, processing a mortgage app, sign in to a site, etc.

Service interfaces of SOA provide loose coupling, which means SOA can be called with no knowledge or little skills of how to implement integration.

Because of the feature of loose coupling, and its way of publishing the services, development teams save their time by reusing the components in other apps in the whole enterprise. This feature serves as both a risk and a benefit.

As a result of the feature of ESB (Enterprise Service Bus), if any issue occurs, other services that are connected to the affected service can also begin to malfunction.

Microservices vs SOA: Similarities of both architectures

Before we start learning about the differences between microservices and SOA, here are three main similarities that make them both look like clones.

• Break the large-scale and complex apps into smaller and flexible components

• Provides better scalability to assist organisations to build and deploy the apps more quickly

• Both Microservice and SOA are agile software development models that are based on hybrid or cloud environment

There are certain similarities between SOA and Microservices. Now, let’s see what are the key differences pf these architectures.

Microservices vs SOA- Key Differences

Here are the 9 differences that you need to learn while debating over SOA vs Microservices. Let’s understand each difference:

Component sharing

As microservices are independent, they hardly require component sharing. It is an advantage of microservices as it can avoid failures of services.

Moreover, the lack of shared components helps developers to easily deploy the latest versions much faster than SOA.

However, component sharing is very common in SOA. Hence, if one service is affected, then other services having shared components will also be affected.

Architecture

In Microservices, the app or software is made up of various small services. Each service performs single functions independently. Hence, in Microservices architecture, there’s minimum sharing of resources between these independent services.

However, in SOA architecture, services are complex and also share more resources than SOA architecture focuses mainly on sharing

which makes the processing slow and also

susceptible to failure

microservices. Here services are dependent on each other.

Granularity

In Microservices, services are granular. It means individual services surpass in carrying out particular tasks. Additionally, combining all tasks can result in a single app.

However, in SOA, the app services are modular and larger and resemble monolithic apps. As each service is scalable, SOA architecture focuses on a broad range.

Scope and Size

While working with the microservices, services are made to perform a specific task & hence the size is smaller and has limited scope. This can be described as services that are customized for that one specific app and cannot be reused.

However, SOA has a larger scope and size and hence allows easy integration of its services. It can also connect services for collaboration of cross-enterprise & hence we can say that the scope is bigger in SOA than in Microservices.

Data storage

In a microservice architecture, every individual service has its data storage. Whereas the SOA approach consists of groups of services to share the same database for storing the information.

The major benefit of sharing the same database makes SOA reuse services and share data in the services.

Cohesion and Coupling

Microservices are based on the aim of bounded context and SOA works on component sharing.

Bounded components means coupling the components and data with a minimum number of dependencies, or where hardly any sharing is needed. This coupling leads to maximum cohesion and hence, the service can be isolated easily from the remaining part of the system (in case it malfunctions).

SOA approach focuses mainly on sharing components and makes the processing slow and susceptible to malfunction. Here, coupling is loosely cohesive, hence issues in one service can cause issues in other services too.

Communication

In SOA, the communication between services is managed using the Enterprise Service Bus (ESB). It acts as a bridge for services to interact with each other.

Contrarily, Microservices rely on easy messaging systems for easy communication.

Deployment

It’s one of the important factors of differentiation between Microservices and SOA. As you know Microservices are independent from each other, they are easy to deploy. While SOA deployments can be more complicated because they are coupled together.

Remote Services

Microservices and SOA both will use different protocols for gaining access to remote services.

The basic remote access protocols used in SOA are MSMQ- Microsoft Messaging Queuing, SOAP- Simple Object Access Protocol, & AMQP- Advanced Messaging Queuing Protocol.

Some of the common protocols in microservices include REST and JMS- that is- Representational State Transfers & Java Messaging Service.

These protocols of Microservices are more equivalent to the protocols of SOA, which are used for heterogeneous interoperability.

Microservices vs SOA- Which one to choose?

Both Microservices vs SOA architectures have their advantages and disadvantages. So how to know which approach will suit your business requirements?

Generally, this decision is taken based on your project’s complexity and diversity. If you have a larger, complex, and diverse app then you can opt for SOA as it can be easy to handle your app that way.

If your app environment is smaller, includes mobile and web apps, and does not need strong communication, you can choose Microservices architecture for it.

SOA vs Microservices- Final Verdict

In the end, the debate of Microservices vs SOA isn’t a one-size-fits-all debate. But it is a question of choosing the correct architectural approach for your business app development.

Microservices can offer agility, fine-grained control, and scalability, and hence can be a good choice for business that has rapid requirements and requires rapid innovation.

On the other hand, SOA provides a holistic and more structured approach to integration and makes it a better option for organizations that require reusability, stability, and well-defined governance.

The final decision of choosing any 1 from SOA and Microservices will decide your business’s future. So, make sure that you are clear with your company’s existing infrastructure, goals, and your app’s nature. Many times, a hybrid approach is also used where both these architectures are combined and a pragmatic solution is provided.

If we conclude the whole article in one order of preference then the order would be -> Microservices > SOA > Monolithic. Bookmark us for regular technical updates. Happy reading!