A database firewall is designed to prevent particular kinds of traffic from passing through the external Internet network to the internal network. This facilitates the database administrators to manage what penetrates in the local network and keep unwanted data out. Besides filtering, this prevents internal users from transferring various forms of data, or transferring data to specified locations.
Application-layer firewalls can recognize the traffic passing through them and permit or refuse traffic based on the data content. Host-based firewalls intended to block unwanted content on the Web that is derived from keywords covered in the Web pages are a type of application-layer firewall. Application-layer firewalls are also employed to examine packets bound for an internal Web server to make sure that the request isn’t indeed an attack in disguise.
At present, the knack to review the contents of a packet is the best way to differentiate between the various firewall products. An Internal Connection Firewall does not have this feature. Though, the majority of business-oriented firewalls do contain this ability.
Application layer filtering is ahead of packet filtering in a way that it facilitates in ensuring more granular control of what data to come inside or go outside of the network. Whereas packet filtering is employed to disallow a specific kind of traffic completely such as- FTP. It cannot make a choice among different FTP messages and decide the authenticity of a particular type of FTP message.
ALF can be employed to search for unusual data in a message’s header and also inside the data itself. Moreover, it can also be used to seek certain strings of character inside the body of a message and block messages on the basis of that information. It is used in combination with the lower layers filtering and offers the maximum possible data security.
Hence, you can employ Application-layer filtering to thwart network attacks, and also stop inside users from transferring any sensitive data outside the network.