One of the more recent evolutions in network security has been the movement away from protecting the perimeter of the network to protecting data at the source.
The reason behind this change has been that perimeter security no longer works in today´s environment. Today, more than just your employees need access to data. Essentially, partners and customers must have access to this data as well meaning that your database cannot simply be hidden behind a firewall.
Of course, as your databases become more exposed to Internet, it is imperative that you properly secure them from attacks from the outside world. Securing your databases involves not only establishing a strong policy, but also establishing adequate access controls.
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