What are service-oriented applications?

The structure and make-up of complex engineered systems are fundamentally different from that of our traditional engineered systems. To model and design these systems, we need an alternative paradigm in system architecture. This system architecture will deal with the high-level complexity of new systems and need to be flexible and loosely coupled. Over the past few decades, a new systems architecture paradigm called service-oriented architecture has emerged within I.T.

What is service-oriented architecture?

Service-oriented architecture (SOA) refers to distributed systems that implement loosely coupled services so we can reuse code. It integrates components via service interfaces and provides protocols for communication, which is done through a service busIt is used to decouple applications and services from each other..

Note: A service is a well-defined, self-contained function that represents a unit of functionality.

Advantages and limitations

There are numerous advantages of service-oriented architecture:

Reusability

Services could be used and reused whenever needed in different contexts and by different applications. This is because of their autonomous, loosely coupled, and self-contained nature. Using existing modules will also reduce development and testing costs.

Maintenance

SOA follows a modular approach which makes maintenance a matter of taking care of individual services without worrying about the rest of the system.

Loosely coupled

With loose coupling, we can easily swap our components since it reduces the dependencies of a class which makes the system more flexible and allows us to refactor code. Code refracting is restructuring existing computer code—without changing the original functionality.

We have seen similar architectures like monolithic and microservices that have tight coupling and decoupling, respectively. In tight coupling, we have classes that depend on each other, reducing code's flexibility and reusability. And with decoupling, there is a lot of uncertainty.

Limitations

SOA also has some limitations:

Complexity

As the system grows larger and more complex, it becomes hard to manage service components, especially coarse-grained and composite services, which also affects the performance.

High cost

SOA needs large investment in terms of technology development and human resources.

Wrap up

It is essential to choose the right architecture before the implementation since it involves factors like investment cost and human effort. It's better to wait and compare the trade-offs of every architectural pattern and choose the right one.