Understanding Amazon SQS Standard and FIFO Queues: Practical Implementation ||aws tutorial beginning

Amazon SQS defaults to the use of standard queues. These queues are capable of handling an almost limitless number of API calls for actions like SendMessage, ReceiveMessage, and DeleteMessage per second. Standard queues ensure at-least-once message delivery, though occasionally, due to their highly distributed architecture and exceptional throughput capacity, messages may be duplicated or delivered out of order. These queues offer a best-effort ordering mechanism, which means that messages are generally delivered in the order they are sent.

Before acknowledging a SendMessage operation, Amazon SQS redundantly stores a message in multiple availability zones (AZs). This redundancy ensures that even in the event of a single computer, network, or AZ failure, messages remain accessible and do not become lost.

FIFO (First-In-First-Out) queues encompass the full set of features found in standard queues but are purpose-built to optimize communication between applications in scenarios where maintaining the strict sequence of actions and events is crucial, or when the presence of duplicates is unacceptable.

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