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SQS vs SNS: Which to Use
We generally recommend SQS, but depending on the architecture of your client application, SNS may be a better fit. We like SQS because of the durability of the integration; if your application has an outage, messages that were sent while your app was down will still be in the queue and can still be processed when your app comes back up. SNS supports pushing real-time messages to your app, but setting up a recurring job or infinite loop to consume SQS messages via long polling delivers messages in near-real-time. For more information on this topic, consider the following posts:
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Sample Photo Status Message
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