What Is a Firewall?
A firewall is a computer program that acts as a gatekeeper for your network. It filters the traffic and matches it against a set of rules. These rules are used to determine whether to allow incoming data or block outgoing traffic.
Firewalls are used in corporate settings. They are usually installed at the perimeter of the network, although they can be installed within the network as well. The purpose of a firewall is to protect the network from attacks.
There are many types of firewalls, including hardware and software. Most operating systems have built-in firewall features. However, firewall software is also available for purchase from your ISP, your hardware vendor, or a third party.
If your organization is in the process of implementing a firewall, you should begin by drafting a service access policy. This document defines the rules that the system administrator can use to access data from the HR database or the code server.
Rules should be realistic, balancing providing users access to network resources while protecting them from known risks. To ensure the rules are up to date, administrators should perform updates regularly.
In addition to protecting the network from threats, a firewall can be used to control the behavior of individual applications. For example, a software firewall can be used to monitor HTTP and FTP traffic.
A firewall can be configured with two basic designs. One uses packet filtering and the other uses stateful inspection. Depending on the design, firewalls may be more or less secure.