A company is building an application to transfer data to a product manufacturer. The company uses its own identity provider (IdP) and requires that the IdP authenticate application users during data transfer. The transfer must use the Applicability Statement 2 (AS2) protocol. Which solution meets these requirements?

AWS Transfer Family supports the AS2 protocol, which is a key requirement for this scenario. It also integrates with custom identity providers (IdPs) through AWS Lambda functions, allowing the company to use its existing IdP for authentication during data transfer. AWS DataSync is primarily for large-scale data migration and synchronization between on-premises storage and AWS, or between AWS storage services, but it does not natively support the AS2 protocol or custom IdP integration via Lambda in this manner. Amazon AppFlow is for integrating SaaS applications and AWS services, not for AS2 data transfers. AWS Storage Gateway connects on-premises applications to cloud storage, but it doesn't support AS2 or direct IdP integration via Lambda for transfer authentication.