Firewalls are one of those things people know they should care about—but often don’t really understand.
So what is a firewall, and why does it actually matter to your business?
At its simplest, a firewall sits between your business and the internet.
It’s the gatekeeper.
The Basics: What a Firewall Actually Does
Every time someone in your office goes online, your firewall is involved.
Most firewalls work on a simple rule:
So if you visit a website, the firewall lets the response come back in.
But if someone on the outside tries to connect to your network uninvited, it blocks them.
That’s your first line of defence.
Why Firewalls Matter More Than Ever
Here’s the bit most people don’t realise.
Your business is already visible on the internet.
There are tools—like Shodan—that constantly scan the entire internet, cataloguing devices, services and systems.
So your firewall has likely already been found and identified.
If something is exposed, those tools can often tell:
You don’t need to be specifically targeted.
You just need to be visible.
That’s why configuration matters so much.
When a Basic Firewall Stops Being Enough
For small businesses, a standard broadband router often acts as the firewall.
That’s fine—until your needs grow.
As soon as you start doing things like:
…you’re increasing your exposure.
And that’s where a proper business firewall becomes important.
Why Firewalls Need Updating
This is one of the most overlooked areas—and one of the most important.
A firewall isn’t just a box.
It’s a computer.
And like any computer, it runs software.
That software can have vulnerabilities.
Manufacturers release updates to fix those vulnerabilities, improve performance and add new features.
If those updates aren’t applied, the firewall becomes a weak point.
Not because it’s badly designed—but because it’s out of date.
Why Businesses Replace Firewalls
Another issue we see regularly is performance.
A firewall that was installed a few years ago might have been perfect at the time.
But things change.
For example:
In those cases, the firewall can become the bottleneck.
The broadband is fast—but the firewall can’t keep up.
Or it simply doesn’t have the features the business now needs.
What Happens If a Firewall Is Compromised?
If someone gains access to your firewall, they’re effectively sitting at the front door of your network.
From there, they can:
In many cases, this isn’t noisy or obvious.
It can happen quietly in the background.
Why This Matters in the Real World
Most security issues we see don’t come from complex attacks.
They come from simple gaps:
That’s why firewalls aren’t something you install once and forget.
They need ongoing attention.
Final Thoughts
A firewall isn’t just another piece of IT equipment.
It’s the boundary between your business and the internet.
When it’s set up and maintained properly, it quietly does its job.
When it isn’t, it becomes one of the biggest risks in your environment.
At Affirm IT, we take a practical approach to firewall security. We don’t start with jargon—we start with simple questions:
From there, we make sure your firewall is properly configured, kept up to date, and doing the job it’s meant to do.
If you’re not sure where you stand, don’t hesitate to
get in touch with us.
