What is the difference between Amazon SQS and Amazon MSK in AWS?

Amazon SQS (Simple Queue Service) is a fully managed message queuing service. SQS is used for decoupling applications and separating microservices, simplifying their interaction. It offers two types of queues: Standard and FIFO. Standard guarantees at-least-once delivery, while FIFO guarantees exactly-once processing in order.

Amazon MSK (Managed Streaming for Apache Kafka) is a fully managed Apache Kafka service. Kafka is a platform for real-time data streaming processing. It is designed for building scalable applications based on data streams, such as metrics collection, logging, event processing, and streaming analytics. MSK provides a scalable, reliable, and accessible platform for Kafka, managing the infrastructure for you.

Main differences:

Characteristic	Amazon SQS	Amazon MSK
Purpose	Decoupling applications, message queues	Real-time data streaming processing
Model	Queue (Pull-based consume)	Publish/Subscribe
Order	Guaranteed as-is (FIFO) or at-least-once	Ordered by partition
Throughput	High, but not for real-time streams	Very high, for streaming processing
Retrieval	Message is deleted after processing	Consumer tracks offset
Complexity	Easier to use	More complex, requires Kafka understanding
Data retention	Short-term (message storage period)	Long-term (configurable period)

SQS is better suited for simple message exchange scenarios between components where strict order or streaming processing is not required. MSK is ideal for building complex streaming data systems where high throughput, reliability, and re-readability are important.

# Example of using SQS with AWS CLI to send a message
aws sqs send-message --queue-url <QUEUE_URL> --message-body "Hello from SQS"

# Example of using MSK with kafkacat to send a message
# Requires configured kafkacat and access to the MSK cluster
kafkacat -b <BROKER_LIST> -t <TOPIC> -P << EOF
Example message for Kafka
EOF