Basic Information
| Field | Details |
|---|---|
| English name | Amazon SNS |
| Full name | Amazon Simple Notification Service |
| Chinese description | 通知与发布订阅服务 |
| Japanese description | 通知・パブリッシュ／サブスクライブサービス |
| Exam frequency | ⭐⭐⭐⭐⭐ |
| Often confused with | SQS / EventBridge |
In one sentence
A managed publish/subscribe service that fans one message out to multiple subscribers.
Key points
- Publishers send to a topic, and SNS pushes messages to subscribers such as SQS, Lambda, HTTP/S, email, or SMS.
- Fan-out commonly uses one SNS topic with multiple SQS queues so each consumer gets its own copy.
- SNS is push-based and does not replace a queue when buffering or independent retries are needed.
Exam takeaway
Subscription filters can route only matching messages to each subscriber.
Update: fan-out and subscription failures
- An SNS topic fans one message out to independent subscribers; combine it with SQS when buffering, retry isolation, and consumption-rate control are needed.
- A subscription DLQ captures messages SNS could not deliver to the endpoint; it is not the consumer’s processing-failure queue.
- Subscription filters reduce unwanted delivery, while filter conditions, retry policy, and target permissions remain separate configuration.