Hands-On RESTful API Design Patterns and Best Practices

The shortcomings of service orchestration

This is a good way to have tighter flow control when there's a need for synchronous communication and processing. There are a few drawbacks with this—if the first service isn't responding, the other services can't be called. That is, it creates a kind of coupling that results in unwanted dependency issues. The orchestrator becomes the single point of failure, and hence the recommendation is to go for clustered orchestration. Synchronous communication blocks other service requests.

The following diagram illustrates how the orchestration process gets accomplished through the participation of disparate and geographically-distributed microservices:

This composition model typically doesn't address failure ...