Final answer:
SSE-S3 encryption uses symmetric encryption where the same key is used for both the encryption and decryption processes.
Step-by-step explanation:
The encryption type used by SSE-S3 is Symmetric encryption. Symmetric encryption is a type of encryption where the same key is used for both the encryption and decryption processes. In SSE-S3, the data is encrypted using a key provided by the user and then stored in Amazon S3, a cloud storage service. When the data needs to be accessed, the same key is used to decrypt the data. This ensures that only authorized individuals with the key can access the data.