A New Solution to Protect Encryption Keys when Encrypting Database at the Application Level

Encrypting databases at the application level (client level) is one of the most effective ways to secure data. This strategy of data security has the advantage of resisting attacks performed by the database administrators. Although the data and encryption keys will be necessarily stored in the clear on the client level, which implies a problem of trust viz-a-viz the client since it is not always a trusted site. The client can attack encryption keys at any time. In this work, we will propose an original solution that protects encryption keys against internal attacks when implementing database encryption at the application level. The principle of our solution is to transform the encryption keys defined in the application files into other keys considered as the real keys, for encryption and decryption of the database, by using the protection functions stored within the database server. Our proposed solution is considered as an effective way to secure keys, especially if the server is a trusted site. The solution implementation results displayed better protection of encryption keys and an efficient process of data encryption /decryption. In fact, any malicious attempt performed by the client to hold encryption keys from the application level cannot be succeeded since the real values of keys are not defined on it.