This is not a new design pattern. It is well known and the most familiar design pattern for Java developers. We already used this pattern in our Legacy/Non-Reactive Systems, which are implemented by using the Servlet API.
Servlets communicate with each other by sending HTTP Request and Response Objects.
In the same way, we use this Request/Response Reactive Design pattern in our Reactive Systems to communicate with its components by exchanging Request/Response Messages, as shown in the following diagram:
As shown in the preceding diagram, Component-1 sends a Request Message to Component-2. Then, Component-2 performs some computation logic and sends the Response Message back to Component-1.
