AWS Integration & Messaging: SQS, SNS & Kinesis

Question 1

What are the two patterns of application communication?

Answer 1

Synchronous and asynchronous communication

Question 2

What issue can arise with synchronous communication between applications?

Answer 2

It can be problematic if there are sudden spikes of traffic

Question 3

What is a scenario that illustrates the need to handle sudden traffic spikes?

Answer 3

Encoding 1000 videos suddenly instead of the usual 10

Question 4

What is a recommended approach to handle sudden increases in application demands?

Answer 4

Decouple your applications

Question 5

What service can be used for a queue model in application decoupling?

Answer 5

SQS

Question 6

What service can be used for a pub/sub model in application decoupling?

Answer 6

SNS

Question 7

What service can be used for real-time streaming in application decoupling?

Answer 7

Kinesis

Question 8

What is a benefit of using SQS, SNS, and Kinesis?

Answer 8

These services can scale independently from our application

Question 9

Entities that send messages to the SQS queue.

Answer 9

Producers

You can have one or multiple producers sending a variety of messages, such as orders to process or videos to handle.

Question 10

These can contain any information that the producer needs to communicate to the consumer.

Answer 10

Consumers

When a message is received, the consumer processes it and then removes it from the queue.

Question 11

What is the purpose of SQS?

Answer 11

The primary role of SQS is to act as a buffer that decouples the producers of messages from the consumers.

Question 12

What is the result of SQS?

Answer 12

By managing different loads and speeds between producers and consumers there is no lose of messages or overloading any component.

Question 13

Features:
- Oldest offering (over 10 years old)
- Fully managed service, used to decouple applications
- Can have duplicate messages (at least once delivery, occasionally)
- Can have out of order messages (best effort ordering)

Answer 13

SQS – Standard Queue

Question 14

Features:
- Unlimited throughput, unlimited number of messages in queue
- Default retention of messages: 4 days, maximum of 14 days
- Low latency (<10 ms on publish and receive)
- Limitation of 256KB per message sent

Answer 14

Attributes of *Standard Queue**:

Question 15

How is a message produced?

Answer 15

Produced to SQS using the SDK (SendMessage API)

Question 16

How long does a produced message persist.

Answer 16

persists in SQS until a consumer deletes it

Question 17

How is a message consumed?

Answer 17

Consumers poll SQS for messages

Delete the messages using the DeleteMessage API

receive up to 10 messages at a time

Question 18

Where do consumers run?

Answer 18

running on EC2 instances, servers, or AWS Lambda