SNS - Simple Notification Service

• It is a highly available, durable, secure, pub-sub messaging service
• It is a public AWS service: requires network connectivity with a public endpoint
• It coordinates the sending and delivery of messages
• Messages are <= 256 KB payloads
• SNS Topics are the base entity of SNS. On this topics are permissions controlled and configurations defined
• A publisher sends messages to a topic
• Topics can have subscribers which will receive messages from a topic
• Supported subscribers are:
  • HTTP(s)
  • Email (JSON)
  • SQS queues
  • Mobile Push Notifications
  • SMS messages
  • Lambda Functions
• SNS is used across AWS for notifications, example CloudWatch uses it extensively
• It is possible to apply filters to a subscriber
• Fan-out architecture: single topic with multiple SQS queue subscribers
• SNS offers delivery status for supported subscribers which are HTTP, Lambda and SQS
• SNS supports delivery retries
• SNS it is a HA and scalable service within a region
• SNS supports Server Side Encryption (SSE)
• We can use cross-account access to a topic via topic policies