Current-day network applications require much more secure data storages than anticipated before. With millions of anonymous users using same networking applications, security of data behind the applications have become a major concern of database developers and security experts. In most security incidents, the databases attached to the applications are targeted, and attacks have been made. Most of these applications require allowing data manipulation at several granular levels to the users accessing the applications—not just table and view level, but tuple level. A database that supports fine-grained access control restricts the rows a user sees, based on his/her credentials. Generally, this restriction is enforced by a query modification mechanism automatically done at the database. This feature enables per-user data access within a single database, with the assurance of physical data separation. It is enabled by associating one or more security policies with tables, views, table columns, and table rows. Such a model is ideal for minimizing the complexity of the security enforcements in databases based on network applications. With fine-grained access controls, one can create fast, scalable, and secure network applications. Each application can be written to find the correct balance between performance and security, so that each data transaction is performed as quickly and safely as possible. Today, the database vendors like Oracle 10g, and IBM DB2 provides commercial implementations of fine-grained access control methods, such as filtering rows, masking columns selectively based on the policy, and applying the policy only when certain columns are accessed. The behavior of the fine-grained access control model can also be increased through the use of multiple types of policies based on the nature of the application, making the feature applicable to multiple situations. Meanwhile, Microsoft SQL Server2005 has also come up with emerging features to control the access to databases using fine-grained access controls. Fine-grained access control does not cover all the security issues related to Internet databases, but when implemented, it supports building secure databases rapidly and bringing down the complexity of security management issues.
