1. Alibaba Cloud.
https://www.alibabacloud.com/help/doc-detail/67829.htm?spm=a2c63.p38356.a1.3.3f341fecRxYbAx
2. Amazon S3.
https://docs.aws.amazon.com/AmazonS3/latest/dev/UsingEncryption.html
3. Microsoft Azure.
https://docs.microsoft.com/zh-cn/azure/security/security-azure-encryption-overview
4. OpenSSL.
https://www.openssl.org/
5. RedLock: Cloud security trends, May 2018 Edition.
https://info.redlock.io/cloud-security-trends-may2018?utm_source=website%20direct&utm_medium=feb2018