Let’s say we have a website hosted on WebServers, and it provides a video processing service. The second set of ASG EC2 will be reading from the SQS Queue and processing data. The WebServer act as producers and put data into SQS queue while VideoProcessing Servers act as consumers. The AWESOME THING, about it is that we can scale the second ASG independently from the first ( & Thats why its called de-coupling)!

And on the top of it, AutoScaling can happen on how many messages there are currently in the Queue of AWS SQS!!