applications1

Question 1

SQS

Answer 1

web service that gives access to MQ. It is a distributed queing system that enables web applications to quickly and reliably queue messages.

Question 2

Why use SQS

Answer 2

decouple so that they run independently easing message managemnet between components

Question 3

Message size in SQS

Answer 3

256KB. But you can go upto 2GB in which case s3 storage will be used.

Question 4

SQS queues types

Answer 4

Standard queues(default), FIFO queues

Question 5

TPS of standard queues

Answer 5

unlimited tps. ensures message is delivered at least once. But occassionally more than one copy of the message may be delivered.

Question 6

FIFO

Answer 6

order is stictly preserved. Exactly one time processing.

Question 7

FIFO TPS

Answer 7

300tps. But have all other capabilities of standard queurs

Question 8

SQS

Answer 8

First service on aws

Question 9

Message retention

Answer 9

1min to 14 days. The default retention period is 4 days.

Question 10

Visibility timeout max

Answer 10

12 Hours

Question 11

Duplicates

Answer 11

After visibility timeout if the message is still not procesed the msg will become visible again and may result in duplicates

Question 12

SQS long poll

Answer 12

doesn’t return a response until a message arrives in message queue or the long poll times out.

Question 13

SWF

Answer 13

web service that makes it easy to coordinate work across distributed application components

Question 14

SWF task

Answer 14

represents invocation of various processing steps in an application which can be performed by executable code, web service calls, human actions and scripts

Question 15

SWF retention

Answer 15

upto 1 year

Question 16

SWF api

Answer 16

presents a task oriented API vs a message oriented api by SQS

Question 17

SWF

Answer 17

ensures task is assigned only once and is never duplicated.

Question 18

SWF actors

Answer 18

workflow starters, deciders(controls the flows), active workers

Question 19

SNS availability

Answer 19

To prevent messages from being lost it is stored redundantly across multiple AZs

Question 20

SNS vs SQS

Answer 20

push vs pull

Question 21

API gateway

Answer 21

Managed service that makes it easier to publish maintain monitor and secure API’s at any scale

Question 22

What can API gateway do

Answer 22

• Expose https endpoint to restful api
• Connect serverlessly to Lambda and dynamoDB
• Send each API endpoint to different target
• scale effortlessly
• Track and control usage by apikey
• Throttle requests to prevent attacks
• connect to cloudwatch to log all requests for monitoring
• Maintain multiple versions of your API

Question 23

API caching

Answer 23

Caches the response to reduce load and improve latency.

Question 24

API caching

Answer 24

Caches the response to reduce load and improve latency.

Question 25

CORS

Answer 25

Cross origin resource policy

Question 26

Amazon Kinesis

Answer 26

is a platform to send your streaming data. Kinesis makes it easy to load and analyze your streaming data and build custom applications for your business needs

Question 27

3 types of Kinesis

Answer 27

Kinesis streams, Kinesis firehose, Kinesis Analytics

Question 28

Kinesis retention

Answer 28

Default 24Hours. Can store upto 7 days

Question 29

Kinesis firehose

Answer 29

There is no data persistence.. lambda is used to process the data

Question 30

Cognito user pools

Answer 30

is user based . It handles things like user registration, authentication, and account recovery

Question 31

Cognito identity pools

Answer 31

authorise access to AWS resources

Question 32

What happens when you create a topic on Amazon SNS

Answer 32

An Amazon Resource Name is created.

Question 33

In SWF, what does a “domain” refer to?

Answer 33

A collection of related workflows