Simple Notification Service (SNS)

Amazon Simple Notification Service (SNS) is a message delivery service provided by Amazon that delivers messages from a publisher to a subscriber. It uses the publish-subscribe model to deliver these messages. In this model, a publisher sends a message to a topic, which is then delivered to all of its subscriber endpoints. Since the publishers and subscribers don’t need to know about each other, Amazon SNS can be used to decouple the components of a distributed system and deliver messages between them.

In Amazon SNS, a topic is a communication channel that receives messages from a publisher and delivers them to all available subscriber endpoints. We can create two types of SNS topics: a standard topic and a FIFO (first in, first out) topic.

Standard topics

In standard topics, messages are sent to the subscribers at least once, and there is no mechanism to preserve the order of the messages received from the topic’s producers. Other than this, in standard topics, there is a chance that message duplicates exist, as a producer might send the same message multiple times to the topic.

Standard topics are used in applications ...