What are Microservices?

In this article, we will be discussing about what is the microservice architecture, why was it needed, its benefits and more… Though we have another blog on microservices architecture as mention in the link https://devopscurry.com/an-overall-guide-on-microservices-architecture/

Introduction to microservice architecture: what is it & why was it needed?

There was once a king who ruled a small, prosperous kingdom with a few loyal ministers. Everything was going well until he decided to expand his territory. He conquered several surrounding kingdoms and his kingdom became an empire. However, with this expansion came new complexities in administration. So to manage this vast empire effectively, he divided it into smaller states, appointing a minister to oversee each one. These ministers further appointed persons responsible for individual departments like tax collection, justice, cleanliness, etc. within their states. As a result, the kingdom thrived once again.

This is also how microservices or microservice architecture was invented. When businesses expanded, it became difficult for the software development team to take care of every small aspect like authentication, payment, user interface, etc. as per the conventional monolithic architecture. So they shifted to a fragmented approach in the form of microservices.

But before moving to what microservices exactly are, let’s first understand the traditional monolith architecture.

Monolithic Architecture: The Conventional Model

Monolithic architecture is a traditional software development model that combines the whole application into a single unified codebase. It’s like the king ruling his smaller kingdom before expansion. That said, it works well for smaller businesses that neither require nor have the resources to appoint an entire team for a particular service.

Monolithic architecture has the following benefits:

• Easy to develop since a single codebase exists that uses the same programming language for coding every component
• Easy to deploy as the application can be deployed as a single unit
• Simple to test or debug
• Cost-efficient as only a single team of developers handles everything

However, this holistic approach to software development and deployment works fine only as long as the business is small, and becomes limiting once the business begins to grow. Following are some limitations of the monolithic architecture:

• As the application and its codebase grow, the development process becomes slower.
• Scaling any components is not possible unless the entire application is scaled up.
• Any bug or error in a single component can affect the entire application.
• To make any change to a single service, the whole codebase needs to be accessed and the entire application needs to be redeployed.

These limitations caused businesses and development teams to shift to an easily scalable, fragmented approach in the form of microservice architecture.

What is the Microservice Architecture?

What did the king do after expanding his territory? He distributed his control among ministers who managed only individual states.

That’s exactly what happens in microservice architecture. The application is distributed into smaller, independent services, each taking care of a specific business function.

Following are some of its important characteristics:

• Loosely-coupled services: The services or the elements of the application are least dependent on each other or in other words, mostly independent of each other. Monolithic architecture had tightly coupled services that prevented the scaling of individual services.
• Specialized services: Each service is responsible for a particular business function. For example, there is a different service for payments and a different one for managing user profiles.
• Well-defined APIs: Application Programming Interfaces (or APIs) allow two components or services of an application to communicate with each other. Lightweight APIs with clearly defined protocols are used for communication between microservices.

Benefits of Microservices

♦ Scalability

In monolithic architecture, scaling individual components without scaling the entire application was not possible. But in microservice architecture, all the components are independent of each other and can be deployed or scaled independently as per requirement. For example, if in an application, there is a sudden spike in payment requests, the microservice responsible for payments can be scaled up. When the requests again go down, the microservice can again be scaled down without interfering with the rest of the application. This helps larger businesses scale individual services on demand.

♦ Flexibility in technology

If the codebase is unified, as in monolithic architecture, all the code has to be in the same programming language. But in microservice architecture, different languages and tools can be used for different services depending on what works best. This helped in enhancing all services without comprising any.

♦ Less risky

Microservice architecture is less risky because its components can be updated or debugged independently without affecting the rest of the application. Moreover, the services can be updated independently without updating the entire application. If there is some issue with an update, the service can easily be brought back to its previous version as well.

Challenges of using Microservices

Complexity in management

Microservices architecture is like managing 10 different applications instead of one. Although it makes individual updates easier, cumulative updates and scaling is time-consuming and complex. It may require specialized monitoring, logging, and orchestration tools to maintainthe integrity of the application.

Performance problems

The individual microservices need to communicate with each other for the overall working of the application. However, a large number of services communicating on the same network can cause congestion and latency, further affecting the performance. Tools like load balancing tools (that distribute network traffic evenly across multiple servers) may be required to reduce response time and network latency.

Expensive

Each microservice requires a dedicated team of developers and tools for its working. This can be costly for newer or smaller businesses. Hence, the microservice architecture is affordable and suitable for only large and well-established businesses.

Conclusion

Both monolithic and microservices architecture have their own benefits and drawbacks. While monolithic architecture is suitable for smaller and newer businesses, microservice architecture is a necessity for bigger and established ones. That said, growing businesses that work on monolithic architecture need to consider their current and future requirements plus their financial situation before making a shift.