Firewall
March 16th, 2009
A firewall is a hardware or software solution to enforce security policies. In the physical security analogy, a firewall is equivalent to a door lock on a perimeter door or on a door to a room inside of the building – it permits only authorized users such as those with a key or access card to enter. A firewall has built-in filters that can disallow unauthorized or potentially dangerous material from entering the system. It also logs attempted intrusions.