A startup company that works on social media apps development would like to grant freelance developers temporary access to its Lambda functions setup on AWS. These developers would be signing-in via Facebook authentication. Which service is the most appropriate to grant secure access?

Answer options:

A.Create user credentials using Identity Access Management (IAM).
B.Use Amazon Cognito for web-identity federation.
C.Create temporary access roles using IAM.
D.Use a third-party Web ID, federated access provider.

Correct Answer – B
Amazon Cognito web identity federation service acts as a broker that allows authenticated users to access AWS resources. After successful authentication on platforms such as Facebook, LinkedIn, or Google Mail, users receive temporary authentication code from Amazon Cognito, thereby gain temporary access.
https://aws.amazon.com/cognito/
Option A is INCORRECT. The access required is temporary and not directly onto the AWS environment. Identity Access Management (IAM) user will be granted access directly using AWS specified credentials.
Option C is INCORRECT. The IAM user credentials will not authenticate on Facebook. They are confined to logging onto the AWS environment.
Option D is INCORRECT. There is no need to take a third-party Web ID from federated access providers since Amazon has the Cognito service to perform that function.