How does each Cloud Service handle BYOK?

To utilize BYOK, the key being used on the cloud must first be imported the Cloud Service Provider, and to import the key, it must first be wrapped. Amazon Web Services takes an AES 256 key that is wrapped by RSA 2048. Google Cloud Platform takes an AES 256 key that is wrapped by RSA 3072. Microsoft Azure takes an RSA key that is wrapped by AES and RSA-OAEP.