Picture this. You’re on your computer at work. You’re searching for a specific piece of information. You click on a link that promises to provide the answer. And then, all of a sudden, your search screeches to a halt. Instead of going to the chosen website, you get a message stating that “in order to protect your computer, this program has been blocked by your firewall.” While it might be annoying in the moment, your firewall has just saved your computer (and your entire system) from potential harm. So just what are firewalls? And why are they an important part of your small business Internet security system?

What is a firewall?

The term “firewall” originally referred to a wall, partition, or barrier that was constructed to halt the spreading of a fire. Built in between buildings (or rooms within a building), the firewall ensured that a fire in one space did not impact another. In our ever-expanding cyber world, there are an increasing number of “fires.” Viruses, worms, adware, spyware, and hackers live in the different spaces of the Internet and are continuously searching for a way to spread into unprotected networks. To help stop the damage created by these criminals, computer programmers looked to the work of architects and developed figurative walls that would stop these destructive fires from spreading.

How do firewalls function?

A computer firewall is placed at the gateway between the public network (i.e. the Internet) and your private one. Firewalls can protect a single computer or an entire office. When a firewall is constructed, it is programmed to follow certain standards. Based on those settings, the firewall monitors all traffic between the two networks. When something from the public network seems fishy or potentially dangerous, the firewall blocks it from accessing your private network. Depending on your settings, the firewall may ask if you want to continue to block the site or whether you want to override the system. In general, firewalls protect against 3 different types of threats.

1. They watch for malware (viruses, Trojans, worms, etc.) that try to enter your system through an Internet connection.
2. They block unauthorized users (such as hackers) from accessing your network through the Internet.
3. They stop malware already in your system from sending out information into the public network.

Are firewalls the only protection I need?

While firewalls are an important part of your Internet security, they do not have the ability to protect you against every threat. For example, they do not stop an employee from clicking on an infected attachment or protect you from someone who gains physical access to your computer. Firewalls work best when they are joined by anti-virus software, strong passwords, and safe Internet practices. Together these programs and activities can keep your entire network safe and sound.