What is Service-Oriented Architecture?
- Service-Oriented Architecture (SOA) is a software architectural style that structures an application by breaking it down into multiple components called services.
- Each service represents a functional business domain.
- In SOA applications, each service is independent and provides its own business purposes but can communicate with others across various platforms and languages.
- SOA components are loosely coupled and use a central Enterprise Service Bus (ESB) to communicate.
What is a microservice?
- On the other hand, a microservice is an architectural style that focuses on maintaining several independent services that work collectively to create an application.
- Each individual service within a microservice uses internal APIs to communicate.
Comparison
- Although SOA and Microservices seem similar, they are still two different architecture types. Microservices are like a more fine-grained evolution of SOA.
- One of their main differences is scope. Microservices are suited to smaller modern web services.
- Each service within a microservices generally has one specific purpose, whereas components in SOA have more complex business purposes and functionality and are often implemented as subsystems.
- SOA is therefore suited to larger enterprise application environments.
- Another significant difference is how both architectures communicate. Every service in SOA communicates through an ESB. If this ESB fails, it compromises functionality across all services.
- On the other hand, services within a microservice are entirely independent. If one fails, the rest of the services remain functional. Overall, Microservices are more error tolerant.
- Today SOA applications are uncommon as it's an older architecture that may not be suitable for modern cloud-based applications.
- However, microservices were developed for the cloud-native movement, and most developers prefer the versatility of service independence they offer.