Readings: AWS: Events

AWS SQS vs SNS

What is the difference betweeen SQS and SNS?

SNS is a distributed publish-subscribe service

SQS is distributed queuing service.

What are some use cases for both SNS and SQS?

SQS : Pull Mechanism — Consumers poll messages from SQS. SNS : Push Mechanism — SNS pushes messages to consumers.

SQS : Messages are persisted for some duration is no consumer available. The retention period value is from 1 minute to 14 days. The default is 4 days.

SNS : No persistence. Whichever consumer is present at the time of message arrival, get the message and the message is deleted. If no consumers available then the message is lost.

AWS SNS and SQS

Describe how to use SQS and SNS in a “fanout” pattern.

In a fanout pattern, using SNS you can send messages yo multiple subscribers and endpoints. This is also a reliable method.

Explain how “push notifications” work, using SNS.

It sends multiple notifications to different devices. It can leverge off of other services to deliever the notification.

SQS and SNS Basics

How might a large scale, distributed application make use of a Queue system like SQS?

It uses the First in First Out queue system to make a priority chain based off of the incoming traffic.