AWS Messaging
AWS Tutorial: AWS Messaging Services Comparison
Welcome to the AWS Messaging lesson. In modern cloud architecture, it is dangerous to have applications tightly coupled together where if one component fails, the entire system crashes.
Why Learn AWS Messaging?
Learning how to decouple applications using messaging services like Amazon SQS and Amazon SNS is a hallmark of a Senior Cloud Architect. It allows your systems to become highly fault-tolerant, scalable, and independent.
Tutorial Overview
In this tutorial, you will learn:
- The concept of Coupling in software architecture.
- Amazon SQS (Simple Queue Service) for message queuing.
- Amazon SNS (Simple Notification Service) for message broadcasting.
Tightly vs. Loosely Coupled
- Tightly Coupled: Application A sends data directly to Application B. If Application B goes offline or gets overwhelmed by traffic, Application A will fail to deliver the data and might also crash.
- Loosely Coupled: Application A sends data to a middleman (a queue). Application B retrieves data from the queue when it is ready. If Application B crashes, the messages sit safely in the queue until B comes back online.
Amazon SQS (Simple Queue Service)
SQS is a fully managed message queuing service that enables you to decouple and scale microservices, distributed systems, and serverless applications. It uses a Pull (Poll) mechanism. Consumers continuously ask the queue, "Do you have any new messages for me?"
Amazon SNS (Simple Notification Service)
SNS is a fully managed messaging service for both application-to-application (A2A) and application-to-person (A2P) communication. It uses a Push mechanism (Pub/Sub). When a message is published to an SNS Topic, it is instantly pushed to all subscribers (which could be an SQS queue, a Lambda function, or an email address).
Exercise
?Which AWS service uses a "Pull/Poll" mechanism to securely store messages until a consumer is ready to process them?