TOOLS FOR INFORMATION SECURITY
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Firewalls
Remember the good days when a firewall was something you found in the front of your Chevy. Well, in today’s high-tech world, a firewall serves the same purpose, but for a network. Much the same as a Firewall is put in a car to provide a point of resistance to a burning or hot engine, a firewall on a network performs the same type of functionality for a computer sys-tem.
There are three main types of firewalls:
1) A packet filter,
2) A hybrid or
3) A proxy. A packet filter firewall examines each IP packet crossing the net-work, and based upon a set of rules, either lets the packet through, or denies access.
A proxy firewall actually acts as a secure gateway between net-works.
The proxy authenticates data and al-lows only specific information to enter or leave the secure side of the proxy. Often times, proxy servers are referred to as application level firewalls, protecting the network (inbound or outbound) depending on the specific application in use. Proxy firewalls are one of the most secure.