1. A Small Requirement We run into small requirements all the time, but they are not always simple to implement. Here is a simple file upload requirement, broken into the following steps: The user uploads a large file on the page The large file is temporarily stored in the internal

1. Where a Message Queue Fits 1.1 Asynchronous Processing Use case: after a user registers, a registration email and a registration SMS must be sent. With the synchronous approach, system performance (concurrency, throughput, response time) hits a bottleneck. 1.2 Application Decoupling Use case: after a user places an order, the