Firewalls for SMBs: What to Know Before You Install One

I get a version of the same slightly-wrong question a lot: "What antivirus do I need?" That’s not quite it. Antivirus protects one device. A firewall protects everything moving in and out of your network, and for a lot of small businesses, it’s either missing entirely or was set up once and never touched again.

What a firewall actually does

A firewall isn’t just "a blocker." Properly configured, it:

• filters inbound and outbound traffic against specific rules, not just an all-or-nothing switch;
• segments your network, so one compromised device: an infected laptop, a poorly-secured printer: can’t wander freely toward your servers or financial data;
• handles VPN access for remote work, without leaving a door permanently open to the internet;
• logs what actually happened, so you can answer "what went wrong" after an incident, not just guess beforehand.

The most common mistake: install it once, forget it exists

A firewall that never gets updated is nearly as risky as no firewall at all. Vendors ship security patches regularly: if nobody’s applying them, known, public, easy-to-exploit gaps just accumulate. It’s that ordinary gap, not the sophisticated attack, that costs the SMBs I work with the most.

What we use, and why

At MPJM, we deploy and manage Fortinet firewalls for most of our clients: a proven platform with real vendor support behind it. For environments that need a more advanced network security layer, we’re also a NextWave partner for Palo Alto Networks. The right choice depends on your size, your traffic, and what you’re protecting, not a one-size-fits-all answer.

What this means for you

A well-managed firewall isn’t a project you finish: it’s a service you maintain: patches applied, rules reviewed as your business changes, alerts actually watched. That’s exactly what’s built into our cybersecurity for SMB service.

Want to know where you stand?

The real question is not which firewall to buy, but what yours lets through today. The free network analysis answers that in writing, along the ten controls behind the MPJM security certificate, and it is offered to businesses with 10 or more workstations, two a month in the order eligible requests arrive.

If you already know nobody is applying the patches, a monthly block of hours sets hours aside each month for your firewall rules and updates, from 125 $ an hour.