Microservices Architecture Vs. Monolithic Architecture, Which One to Choose and Why?

All Big Giants, including Netflix, Uber, eBay, Amazon, Twitter, PayPal, and more, have already consummated value for money after using a microservices architecture. You would be surprised to know that Netflix, the fastest-growing company is one of the earliest adopters of Microservices architecture. Uber, initially used monolithic architecture, but soon shifted to microservices. Do you know the reason why? To find out the answers to all of these questions, including, “why should you use Microservice architecture for your software development?”, Keep reading this blog.

Microservices is a development technique, a variable of Service Oriented Architecture(SOA), that assists in developing large applications where you can arrange and divide services into small independent chunks depending on the domain. In a microservices architecture, the services are fine-grained, and the protocols are lightweight.

The tangible benefits of adopting this microservice architecture are, increase in scalability, modularity, availability, agility, flexibility, and others. For the very obvious reasons, the microservice approach is getting maximum traction these days. Ever since the term came into the picture, it is laying the foundation of resilient software development.

Microservices is helping developers to understand the complex application process better and deliver it faster after effective testing. To be honest, you just can not ignore this whole buzz going around the microservices architecture at all, can you?

Before we deep dive into the microservice architecture, it would help if we know the details of the contrary approach, which is monolithic architecture.

Wikipedia’s definition of monolithic architecture,

In software engineering, a monolithic application describes a single-tiered software application in which the user interface and data access code are combined into a single program from a single platform.

It is a traditional way of building applications usually comprises of a client-side user interface, server-side architecture, and a database. The architecture has a huge codebase but with no modularity. This means, if you wish to make any changes in the codebase then, you will have to go through the whole stack of code and make changes in it.

The monolithic approach uses a three-tier architecture, which is given below.

Presentation Layer: The first layer that describes the user interface, which is written in HTML, Javascript, or CSS. It interprets the code and gives an understandable output for the client.

Business Layer: It is the middle layer where the data processing takes place for making logical decisions and calculations.

Data Access Layer: This is the final layer from where the data is passed to the user. In the Data Access Layer, the information is stored and retrieved from the database.

In simple words, the client query is received through the application, passes through the business layer for logic execution, stored in the Data access layer, and presented to the user in the Presentation layer. This traditional approach of software development was welcomed until the demand rose for continuous delivery. It proved to be inefficient in handling the continuous delivery demand.

Strengths of Monolithic architecture:

Easy debugging and testing:

It is possible to run end-to-end testing on apps built using monolithic architecture. Monolithic architecture facilitates easy debugging and testing of applications.

Easy to deploy:

A major advantage of using monolithic architecture is the easy deployment of the application. Instead of multiple files, you just have to deploy one file or a directory.

Ease of development:

Monolithic software application development follows the standard and basic way of building. Any developer or company can easily adapt the same in their organization. Additionally, it is easy to handle the cross-cutting concerns of the application.

Pitfalls of Monolithic architecture:

Scalability:

Since it is a single platform-based, it is difficult to scale the individual component of the application. Hence, you have to scale the entire application, even if it is not required.

Understanding:

The monolithic architecture approach is complex, and it is difficult to understand the complexity of the application once it is built up. Additionally, it is a real hassle to manage and maintain the complex single codebase.

Difficult to implement changes:

Unlike microservice architecture, the monolithic services are tightly coupled. Hence, for making any changes in individual service, the whole system has to be taken into consideration. This further means that, for existing applications, the entire system has to be put on hold unless the changes are made, and a new version is released.

The autonomy of the software stack:

It is challenging to implement new technology because the entire application has to be rewritten again. Only a single framework is used, and if it is not updated then, the whole application’s code will become obsolete within a short time.

Building apps using the monolithic approach is a costly affair for a software development company. Because everything is mixed in a single source file, it is difficult to maintain the software, and it further increases its time-to-market. We are sure; no one would be able to afford this loss of sales because of the increased application development time.

These risks and upfront costs lying ahead of a software development company compelled developers to find a different approach to building.

Microservice architecture came to rescue for such scenarios. The approach revolutionized the way an application is built, (all positively) and helped software companies to outshine the competitors.

We already gave you a brief about microservices architecture and its capabilities to gracefully handle the system errors and issues. It is a collection of individual services that are loosely coupled. It is easy for developers to communicate with a microservices approach and carry out each task effortlessly.

The reason being, each of the services acts as mini-applications that are developed separately by the team of developers. The team can individually perform their task of services development and deploy them at the decided time.

Say, for example, you are developing an on-demand pharmacy application that needs a user side component, the delivery boy-side component and the vendor-side component. For the general case, it may happen that we need to fetch data from multiple components at a single request.

Microservices architecture helps in fetching these responses instantly from various components and makes an app capable of handling multiple requests. This is a major difference between monolithic and microservices architecture. The monolithic application may not be able to handle the queries efficiently.

Thus you can say, microservices methodologies follow the Unix philosophy of “Do one thing, but do it well”. Here is the list of characteristics of microservice architecture based applications.

The services run on independent components;

The services are organized as per business capabilities;

It prefers product over process;

The application development approach has smart components which use simple communication channels like REST protocol;

There are no centralized standards but decentralized governance for data management. Every individual component follows its exclusive standard for development and deployment.

It has automated infrastructure management, which helps in reducing the complexity of the project;

The design and feature can easily be updated without affecting the whole application because of the flexibility of the architecture;

Every service is elastic, resilient, composable, minimal, and complete.

These all being said, there is more to the story which will compel software developers and development companies to invest in microservice architecture:

Improves fault-isolation:

In a complex application architecture, if anything goes wrong, it is difficult to trace it back. But with this approach, a developer can easily know where they should be looking for the issue. Since the whole structure is divided into multiple microservices, an affected service part can easily be identified and promptly be resolved.

This is where a monolithic architectural app fails to deliver in. You can not put the application at risk at the cost of individual service.

Ease of adopting a new technology stack:

The service components are loosely coupled, which allows you to try a new technology stack on individual components. If that is a success for you, then you can implement the same over a large application level. Additionally, with microservices, there is no dependency issue, and therefore, why you are implementing a new technology stack in one component, the user experience is not disturbed, and it remains consistent across.

Scalability:

Microservices architecture improves the overall performance of the application. You can use more containers or plan an effective capacity planning along with less licensing cost and appropriate use of hardware. The critical services can always be looked into, and the performance of the app can be improved. Hence, the application is able to deliver consistent user-experience always, with time and money savings.

Enhanced productivity and Speed of development

Microservices architecture gives you an easy way out to increase the productivity and speed of development. Since the service components are divided, each team can work individually on it without waiting for the other team to finish the work. Also, if a service component is ready, the team can send it for testing to the QA teams. This activity speeds up the process immensely, and the company can expect a faster development of a product.

Proper distribution of the task and alignment with the organization:

Since the work will be divided into individual units, it would become easy to define the team requirement. Each of them would focus on the management of a single component and deliver consistent user experience. For instance, the UI team shall focus only on designing a great UI, and the backend team can work upon the component irrespective of the prior one.

Pitfalls of Microservices architecture:

It is not that the microservices approach is flawless, but it has its own set of problems. Let’s have a look at the areas where microservices architecture falls short.

No doubt, microservices architecture reduces the complexity of the software development process, but each of the requests made between the components has to be handled carefully. The teams have to communicate with each other about the updates or the bugs in a particular component; otherwise, the whole application may get affected if performed wrongly.

Additionally, testing of the connected services can be a problem. The reason being, each component developer, has to confirm their status before the testing starts. The constant surveillance over all tabs is practically impossible and may result in database errors, network latency, caching issues, etc.

Each of the components needs to keep its schemas and interface documents updated.

To handle application complexities at various stages, you need an expert team to handle the DevOps.

Since all the components rigorously communicate with each other, you need reliable and fast network connections.

The upfront cost of application development can be higher as compared to the monolith architecture.

You may fall short of tools to carry out adequate testing of each component.

You need robust monitoring to track down the issues of individual components.

However, the drawbacks of the microservices architecture are quite negligible as compared to its advantages in current times. The speed of development and delivery in no time has made software development companies deliver a robust application in just a snap of fingers.

What is the difference between Monolithic architecture and Microservices architecture?

We suppose the following table will be able to conclude the thoughts for you. Keep reading further….

So, now let’s answer the question we have mentioned above, Why did Uber, who started its journey with a monolithic architecture, shifted to microservices architecture?

The answer to this question is, initially, Uber was built to provide service in a single city. Since the app was planned to handle the operations of only one city, the single code-based approach looked feasible and easy. But very soon, the popularity grew in leaps and bounds, expanding the services to various other cities. The service components became dependent on each other, and continuous integration became difficult to follow. And hence, there arose a need to adopt a microservices architecture.

1. Uber initiated an API gateway which connects all the users and the drivers;

2. It deployed separate units for performing various functionalities;

3. The app became more scalable.

Ready to make a choice?

Just like a coin has two sides, both the architecture approaches have its advantages and disadvantages. Even a monolith architecture approach has its strong and durable benefits, which can be immensely useful depending on the project type. Say, for instance, you are starting with a brand new app, then you should validate it first using a monolithic architecture approach.

For small scale software development, monolithic architecture is best, and for large scale applications, microservices architecture is more suitable.

It wouldn’t be wrong to guess that, very soon, the monolithic architecture approach will be used for product prototyping. For any other queries, you can have a word with our technical experts, or you can hire our app developers for your next project.

ABOUT THE AUTHOR

Manav Patel

Founder