Since cloud storage becomes a major application in cloud computing, many
researches have been focusing on how to protect and verify the data stored in the Cloud.
There is a problem that the owner doesn’t want the real data stored by the Cloud to
be Cloud known. Therefore, the most popular way is to encrypt entire file by using
a secret key like Amazon Simple Storage Service (S3) [1]; however it may bring some
problems such as secret key change and distribution, key management, and access rights
management. So, we propose a hierarchical key management scheme to solve the problems
mentioned above. And this scheme is suitable for individuals or enterprise service
providers to manage their keys of files, software, and services.
