Principal ID: For Principal ID based authentication choose Principal ID to grant access for permission and External ID. The Principal ID and External ID will be required for configuring permissions in your AWS Account. For more information, see Cross account access in AWS. When using the Principal ID option, use AWS Account ID 902917483333 to grant the access permissions. As part of permission required for credentials, provide at least read-only permission to the AWS user whose credentials will be used.
https://docs.infoblox.com/space/BloxOneDDI/512098335/AWS+-+General