SNS + SQS: Fan-Out Pattern

• Publish a message once to an SNS Topic, and it is delivered to all subscribed SQS queues.

• Enables a fully decoupled, reliable architecture with no data loss.

• SQS ensures:
• Persistent message storage.
• Delayed or scheduled processing.
• Automatic retries for failed processing.

Benefits

• Easily add new SQS subscribers without modifying the producer.

• SQS access policies must permit the SNS topic to publish to the queues.

• Supports cross-region delivery, allowing SNS to send messages to SQS queues in other AWS regions.