You are a Solutions Architect in a startup company that is releasing the first iteration of its app. Your company doesn’t have a directory service for its intended users but wants the users to sign in and use the app. Which of the following solutions is the most cost-efficient?

Answer options:

A.Create an IAM role for each end user and the user will assume the IAM role when he signs in the APP.
B.Create an AWS user account for each customer.
C.Invest heavily in Microsoft Active Directory as it’s the industry standard.
D.Use Cognito Identity along with a User Pool to securely save users’ profile attributes.

Correct Answer: D
Option A is incorrect. It is improper to assign an IAM role for each end-user. IAM role is not a directory service.
Option B is incorrect. AWS account cannot be configured as a directory service.
Option C is incorrect. This isn’t the most efficient means to authenticate and save user information.
Option D is correct. Cognito is a managed service that can be used for this app and scale quickly as usage grows.
References:
https://aws.amazon.com/cognito/
http://docs.aws.amazon.com/apigateway/latest/developerguide/apigateway-integrate-with-cognito.html
https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-identity-pools.html
https://aws.amazon.com/cognito/getting-started/
https://docs.aws.amazon.com/cognito/latest/developerguide/concepts.html