How Does a Firewall Work?

A firewall works like a security gate for your computer. When it is installed, it allows certain information to pass through if that information is safe and trusted. If information is not trusted or if something tries to pass through that does not belong, then the firewall stops it in its tracks. 

A firewall is an installed feature on a computer network that has access to the Internet. Firewalls are basically named after their function, as they work as a digital blocker for harmful material trying to enter a network from the Internet. Firewalls monitor information in and out of your computer to keep your personal information safe.

Every website on the Internet carries with it a signature, and sends out information in what are known as packets. These packets contain data that is coded in a manner that is either trusted or distrusted by the firewall settings, depending on the parameters set by the user.

If the packets contain data profiles that aren’t programmed to be trusted by the firewall, the trusted information is allowed to access the network and all of the distrusted content is blocked and discarded. The filter works by siphoning all of the coded information as it gets to the firewall, deciphering the coded information and identifying any codes or programming anomalies that may represent a threat to the system. The firewall seeks these distrusted codes out of the packet information and then checks them against the system parameters to determine whether or not to allow the information through the firewall.  The firewall works in order to keep websites that pose a threat to the network from accessing the network or any information contained within it.

Firewalls often are the first line of defense in many Internet-based systems, acting as a filter for flagged items. If the information entering the network has any flagged coding in its signature, the firewall prevents the information from entering the network. 

Getting a Firewall

Now that you know how a firewall works, you may wonder about whether you have one or how you can get one.

• Most operating systems contain a firewall within them, especially those that include a web browser program, or those that are designed to work in business formats.
• Home networks, whether they have broadband or wired Internet connections, are also vulnerable to harmful websites and the damage they can inflict, so home users also need protection from a firewall.
• Firewalls can be purchased in the form of either computer software programs or physical hardware devices that are installed or incorporated into Internet-based systems.

No matter what the methodology of the installation, firewalls are an essential element in any type networking technology. The determination as to whether or not you should buy a software or hardware firewall depends on the intended usage of the network, as well as the number of stations or computers within the network that will have Internet accessibility.

In home networks, most of the available operating systems have sufficient firewall technology included, but an added antivirus program that includes a firewall feature is also recommended.