Data security in medical information system

The database systems use the mechanisms of granting and revoking privileges and of authorization control to ensure the security of data. However, some users such as administrators or persons in charge of security have access to comprehensive content of database including patient´s information that are of intimate nature and must be discreet. To enhance the security and avoid illegal access of such users, we propose in this article a mechanism using the content-based watermarking technique. Patient´s information are encrypted and inserted in an image associated to it. This image, with faculties of object-relational and object-oriented databases, is directly integrated into the database. To check the integrity of the image we use the edge map and invariant moments.