Which solution will meet these requirements?
Create a user cookie. Attach an 1AM role to the S3 bucket that hosts the application.
Deploy an Amazon CloudFront distribution with an origin access identity (OAI) to access the S3 bucket.
Configure and use Amazon Cognito. Access DynamoDB with the authenticated users.
Create an IAM user for each user. Use fine-grained access control on the DynamoDB table to control access.
Explanations:
Creating a user cookie alone does not solve the issue of uniquely identifying users at scale, and attaching an IAM role to the S3 bucket does not address user authentication or secure access to DynamoDB.
Deploying an Amazon CloudFront distribution with an origin access identity (OAI) improves access to the S3 bucket but does not address user identification or secure access to DynamoDB.
Amazon Cognito provides authentication, user management, and identity federation, which helps uniquely identify users at scale and allows secure access to DynamoDB.
Creating an IAM user for each user is not scalable and would be cumbersome to manage for 10,000 users. Additionally, it complicates managing access to DynamoDB for individual users.
I gauge that the answer is:
Configure and use Amazon Cognito. Access DynamoDB with the authenticated users.