You'll get confused between microservices and SOA if you don't have a complete understanding of both. On the surface, the microservice features and advantages sound almost like a slender version of SOA, with many experts suggesting that there is, in fact, no need for an additional term such as microservices and that SOA can fulfill all the attributes laid out by microservices. However, this is not the case. There are enough differences to isolate them technologically.
The underlying communication system of SOA inherently suffers from the following problems:
- The fact that a system developed in SOA depends upon its components, which are interacting with each other. So, no matter how hard you try, it is eventually going to face a bottleneck in the message queue.
- Another focal point of SOA is imperative monogramming. With this, we lose the path to make a unit of code reusable with respect to OOP.
We all know that organizations are spending more and more on infrastructure. The bigger the enterprise is, the more complex the question of the ownership of the application being developed. With an increasing number of stakeholders, it becomes impossible to accommodate all of their ever-changing business needs.
SOA uses an enterprise service bus (ESB) for communication; an ESB can be the reason for communication failures and can impact the entire application. This could happen in a scenario where one service is slowing down and communication is delayed, hampering the workings of the entire application. On the other hand, it would not be a problem in microservices; in the case of independent services, if one service is down, then only that microservice will be affected. In the case of interdependent services, if one of the services is down, then only a particular service(s) will be affected. The other microservices will continue to handle requests.
Data storage is common/sharable in the case of SOA. On the other hand, each service can have independent data storage in microservices.
This is where microservices clearly stand apart. Although cloud development is not in the current scope of our discussion, it won't harm us to say that the scalability, modularity, and adaptability of microservice architecture can be easily extended with the use of cloud platforms. It's time for a change.
Let's look at the prerequisites of microservice architecture.