04/12/2021

IOS KingMan

IOS KingMan

What is a firewall? Understanding the security measure that protects against cyber threats

  • A firewall is a key cybersecurity feature for protecting a home or office network from malware and other online threats.
  • There are distinct forms and types of firewalls, and some are considered more secure than others. 
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Many of us live with the fear of a cyberattack disrupting our computer-dependent lives — not to mention their potential to wreak havoc on an entire country.

Fortunately, we have security measures like firewalls, which prevent bad actors from gaining unwanted access to networks. 

Preventing your internet from crashing isn’t the only positive you can gain from a network firewall. There are also customizable uses for firewalls, like blocking inappropriate online content from your children. 

Here’s what you need to know about firewalls, including how they work and why they’re important.

Firewalls, explained

A firewall is like a bouncer for your internet activity, creating a security barrier between your home network and unwanted intrusion from the internet at large.

Firewalls can be cloud-based, or they can be a physical piece of hardware that you buy and connect to your modem and router. (For the most part though, modems and routers will come with pre-implemented firewall technology.)

If you’ve ever tried to set up your own server with port forwarding, for instance, you may have been foiled by your router’s firewall.

A firewall can protect all your family’s devices.
Stephen Swintek/Getty Images

Your computer will also in all likelihood come with its own proprietary firewall, like the Windows Defender Firewall that comes installed on Windows PCs.

There are many types of firewalls, but the gist of how they work is similar: a firewall works by closing your network off by default to most internet traffic, or at the very least, requesting your permission before allowing the traffic in.

Why firewalls are increasingly important 

Having some kind of firewall as a line of defense for your home network has become increasingly important as more devices are internet-enabled. After all, you don’t want to worry that your porch’s smart light bulb — which you installed as a means to dissuade burglars — is creating a cybersecurity loophole in your network.

A firewall acts like a shield for your internet network and devices.
sarayut Thaneerat/Getty Images

There are benefits beyond security as well: A properly configured firewall can keep your internet running more quickly by routing traffic more efficiently.

Finally, a firewall can also be programmed to act as a content moderator for kids by restricting their access to certain websites. Those sorts of settings won’t be standard for a firewall, but can be configured with most of them.