Firewalls: what they are and why you need one

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Internet connections are not one-way streets. Websites “talk” to your computer, sending and receiving information.

But is there any way to tell if the information source is dangerous? If it is, how do you stop it from sending malware or stealing your information?

Firewalls were invented to tackle these exact concerns. They work as your first line of defense in keeping the bad guys out of your network. But how do they work? How do you know if you need one?

For over 25 years, WEBIT Services has helped hundreds of clients find the best cybersecurity tools, systems, and practices for their businesses.

By reading this article, you will learn what firewalls do, how they’ve evolved over the years, how to tell if your firewall is effective, and how to know if you need a firewall.


What is a firewall?

A Firewall is a network security device that monitors and controls incoming and outgoing data based on the rules and parameters you set.

In essence, it acts as the “front door” to your network and is your first layer of cybersecurity. It helps keep the bad guys—or, more accurately, their malignant software—out of your network.

Firewalls deny access to data from specific IP addresses (a unique ID given to a device when connecting to the internet). These may be IP addresses from an embargoed or the known IP address origin for malware or viruses.

For instance, your IT provider may learn about a new computer virus. Cybersecurity systems can identify the IP address receiving data from the activated virus. Now, your cybersecurity expert can set firewalls to block anything coming from that IP address.

However, firewalls are not antivirus software. While they are becoming more advanced and can, to a degree, identify what information is coming through, they do not identify viruses and malware attached to bad links or emails.

Instead, firewalls block sites or emails from identified dangerous sources.

For example, if we think of firewalls as a front door, you may be able to look through your peephole or Ring Doorbell to see if a package was delivered. You can see that it’s an Amazon package, but not what’s inside the box itself.

In this same line of thought, you can also see who the package is from and its appearance. You may open an expected Amazon package, but you’re unlikely to open a suspicious box with no return address.

Firewalls work the same way with data: information coming from dangerous, suspicious, or unwanted sources are blocked to help keep your network safe.

The firewall may be unable to identify what’s IN the data “package” but knows it comes from a dangerous source. Therefore, the firewall doesn’t even let the package through the door.

Blocking applications

You can also program a firewall to block applications within your network.

For instance, some offices will allow remote logins to your laptop. Your firewall can be programmed to only allow remote access for users actively using your office internet connection. Anyone outside your network will be blocked.

This prevents cybercriminals from breaking into company hardware using remote access.

Or, maybe, you’ve found specific applications negatively impact productivity or carry malware. You can program your firewall to block those applications. In this case, employees cannot access these applications while connected to your network.


How firewalls have evolved

In the early days of firewalls, they were programs that “set it and forget it.” You could program the firewall to deny all data from specific sources. They were not “intelligent” or speedy programs.

Firewalls’ improved speed and intuition

Now, firewalls are “smarter” programs that can inspect data faster. They are speedy and can better evaluate data packets to determine if they’re coming from a dangerous source, even if that source has not been blacklisted.

Again, thinking of firewalls as a door, the firewall has evolved from a peephole to a door attendant.

While the peephole previously allowed us to see a package was delivered, our attendant now examines the box to see if it’s from a trustworthy source. If it seems suspicious, the attendant will withhold it unless told otherwise.

Again, in previous years, this level of intuition slowed firewalls down. It took time to evaluate the data source. In fact, it took so much time that few people considered it worthwhile.

Now, firewalls can process information quickly without taxing internet speeds.

Updating firewalls

In earlier years, you set up a firewall to block specific sites or sources, and it was good to go. You didn’t have to think about updates.

However, current firewalls have regular system updates to improve them. These updates include IP block lists of the most recent threats.

They have also become incredibly complex programs that need regular maintenance and updates to help keep them functioning at their best. They can slow down your system or let in dangerous data if they are not maintained.

Firewalls are often examined as a part of your IT provider’s on-site maintenance visits and quarterly risk assessments.


Is my firewall effective?

While having a firewall is essential, it is equally important to ensure it’s working correctly.

A properly programmed and maintained firewall offers efficient protection. However, a poorly configured or poorly maintained firewall can cause frustrating complications for users.

Slow connections

A poorly programmed or mismatched firewall can slow down your internet. It won’t matter how much internet speed you purchase; an incompatible firewall will cause data to download at a snail’s pace.

If a slower or older firewall is set to examine every packet of data closely, it can create a bottleneck effect on your internet.

In this circumstance, your firewall needs to be faster to match your internet speed and expectations. Or you can adjust the settings, so it only examines incoming data from suspicious sources.

The less the firewall has to investigate, the faster it lets data through.

Poor functionality

Firewalls blocks designated applications or data from specific sources. However, if your firewall was incorrectly configured, it may block the data and applications you need.

Your IT provider or internal IT department can correct this by updating your firewall settings to include data from these sources and applications.


Firewalls can develop vulnerabilities if you don’t run system updates and regular maintenance.

For instance, it won’t block new IP addresses because it never received the information in the latest update.

If your IT provider or internal IT department is not actively updating your firewall, it may not be working at its full capability.


How to check your firewall

To make sure your firewall is doing its job, your IT provider or internal IT team will need to do an assessment. This will be a deep dive examination to see if there are gaps in the firewall’s security settings.

In these assessments, your firewall will be turned off, and, as such, so will your entire network. As a result, your network disconnects because everything moves through the firewall.

Your IT provider or internal IT department will perform these assessments during approved, scheduled times so they won’t interfere with your company’s productivity.

Some businesses will utilize two firewalls to avoid shutdowns. In this circumstance, one firewall is active, and the other is passive. They all see packets simultaneously, but only one is working. If one fails, the passive one becomes active and takes over.


Do I need a firewall?

You may say, “I’ve never used a firewall before. Why do I need one now?”

Cyberattacks grew by 92.7% in 2021 alone. With this growing threat, many companies seek every defense they can utilize against cyber threats.

Because it acts as the front door to your system, your firewall is your first line of defense. Firewalls help keep dangerous sites and data out of your system and help reduce your risk.

However, depending on the kind of data your business finds valuable, you might not need a firewall. You do not need a firewall if you do not connect to the internet.

However, if you connect to the internet and don’t want to put your data at risk, a firewall is a valuable asset. Firewalls are also a compliance requirement for regulated industries like finance and healthcare.

Again, looking at a firewall as a door, you may not need a front door to certain “buildings.”

For example, the old shed in your backyard holds no valuables; therefore, you may not want to pay to install a door. However, you most certainly want a secure front door in your home.


Next steps for evaluating your firewall

Firewalls are complicated but beneficial assets in your cybersecurity system. They act as the front door to your network, blocking data from harmful sources.

When properly programmed and maintained, they create an effective first line of defense for your company.

However, incompatible, poorly programmed, and ill-maintained firewalls can cause frustrating delays and complications.

Discussing your firewall’s effectiveness with your IT provider or internal IT team is important. To assess your firewall, you can ask:

  1. What is my firewall doing? Is it protecting us as it should?
  2. How fast is my firewall? Is it compatible with my internet connection, needs, and expectations?
  3. Could my firewall be doing more to protect my company?

If the answer to questions one and two are "Yes," and the answer to three is "No," then you have been matched with an effective firewall. If not, it may be time to discuss changing firewall subscriptions.

In addition, your firewall should be part of regular IT maintenance and risk assessments. If it is not, this could be a red flag for poor IT service.

WEBIT Services has improved cybersecurity systems for hundreds of clients in the Chicago area.

If you are looking for a new IT provider or have questions about cybersecurity, schedule a free 30-minute consultation to see how WEBIT Services can help.

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