The term “firewall” has been around for a long time — originally, it had nothing to do with technology. Rather, it was a construction term referring to the walls of buildings built with the specific purpose of preventing fires from spreading inside a structure.

These days, it’s most often heard in connection with computer networks. But the concept is the same: a computer firewall also acts as a barrier. Except in this case, it’s a barrier between a trusted network (office, home, etc.) and the outside, greater Internet.

Firewalls are an essential tool in the never-ending battle to protect against bad actors. So it’s important to understand how they work and what your options are.

First, an (oversimplified) Explanation of the Pieces Involved…

A firewall is one of five discreet functions that work together in allowing safe and efficient communication between your devices and the outside world. These functions exist in both residential and business settings.

In your home, they are typically built into one or two physical devices made available by your Internet provider. In an office setting, they may each have their own appliance. Whatever the specifics, five elements come into play:

1. Modem (bridge). Converts a signal from one type of medium to another. For example, in your home, the Internet may arrive via a fiberoptic cable. Your network can’t use it in that form, so the modem (short for “modulate/demodulate”) converts the signal to something it can interpret.
    
2. Router. As the name suggests, the router directs communication between the “highway” (the Internet) and a “street address” (your network and devices), in either direction.
    
3. Network switch. This splits the signal from the modem and sends it to various wired connections (if you look at the modem in your home, you likely have four slots into which you can plug ethernet cables).
    
4. Wireless access point. Conceptually similar to a network switch, except this is what allows your wireless devices to connect to the network.
    
5. Firewall. A barrier that determines what traffic is allowed to come in and go out.

Why a Firewall Matters

In its most basic form, a firewall blocks all inbound traffic from the Internet and permits all outbound traffic going in the other direction. Some businesses employ additional restrictions (more on that below), but that’s fundamentally what is going on.

Of course, you can still browse web sites, watch movies on Netflix, conduct Zoom calls and more. But that’s not “inbound traffic.” In those cases, you are expressly establishing a temporary channel and “inviting” those signals in.

It’s also why, since firewalls allow all outbound traffic, absent additional protections, your own employees can wreak havoc within your network by visiting a “bad” web site. Here as well, they are establishing a temporary channel, effectively opening the door and letting a stranger come right in.

Your Organization Needs a “Business Class” Firewall

I have written before about the importance of business class equipment and support for an organization. When it comes to running a company, the devices and services supplied by your cable provider or that you purchase at Best Buy or on Amazon are not up to the job.

The same applies to why you need a business class firewall. It offers superior:

• Protection. The software code built into the firewall is what keeps the bad actors out. If there are bugs or other weaknesses — as is often the case with consumer-grade products — they may be exploited. Business class software is higher quality, plain and simple.
   
• Capacity. Inspecting inbound traffic takes time. The bandwidth limitations of consumer-grade firewalls are much greater than those of business class, which are built to scale to higher speeds.
   
• Specialized Filtering. Business class firewalls offer a great deal of configuration flexibility and, therefore, protection. For example, they allow your administrators to restrict which sites or types of sites your employees may visit (i.e., which “doors” they can open), reducing the likelihood that careless or inadequately trained staff may cause harm.
   
• Support. Support is like insurance — it doesn’t matter until it does. When you’ve got a problem that needs fixing, you don’t want to wait for hours just to get to somebody that’s reading from a script. You want someone that really knows the product. That’s part of what you are buying with a business class firewall.

It Only Takes One Mistake

Unlike many other functions within your business, cybersecurity can’t afford to be “mostly effective” — it has to be perfect every day. It only takes one breech, virus, or malware infection to cause extensive damage and the bad guys are at it 24/7.

Your firewall is a critical tool in the mix. Make sure it’s operating as it should and at the (business class) level you require.