Which authentication approach would meet these requirements with the LEAST amount of effort?
Configure the services to use Amazon Cognito.
Configure the ALB to use Amazon Cognito.
Configure the services to use AWS Security Token Service (AWS STS) with the OpenID Connect IdP.
Configure the Amazon ECS cluster to use AWS Security Token Service (AWS STS) with the OpenID Connect IdP.
Explanations:
Configuring the services to use Amazon Cognito would require integrating Cognito directly into each individual service, adding complexity.
Configuring the ALB to use Amazon Cognito allows for easy authentication with OpenID Connect-compatible IdPs, requiring minimal changes to services.
Configuring the services to use AWS STS with an OpenID Connect IdP would involve complex token management at the service level.
Configuring the ECS cluster to use AWS STS with an OpenID Connect IdP does not address the authentication requirement at the ALB level.