User
Properties
The external ID is a value. We recommend you use ExternalId to add security to your IAM role, which is used to call Amazon SNS to send SMS messages for your user pool. If you provide an ExternalId , the Cognito User Pool uses it when attempting to assume your IAM role. You can also set your roles trust policy to require the ExternalID . If you use the Cognito Management Console to create a role for SMS MFA, Cognito creates a role with the required permissions and a trust policy that uses ExternalId .
The Amazon Resource Name (ARN) of the Amazon SNS caller. This is the ARN of the IAM role in your AWS account that Amazon Cognito will use to send SMS messages. SMS messages are subject to a spending limit .
The AWS Region to use with Amazon SNS integration. You can choose the same Region as your user pool, or a supported Legacy Amazon SNS alternate Region . Amazon Cognito resources in the Asia Pacific (Seoul) AWS Region must use your Amazon SNS configuration in the Asia Pacific (Tokyo) Region. For more information, see SMS message settings for Amazon Cognito user pools .