Emerging Threats

What is a firewall?

A firewall is a security device — computer hardware or software — that can help protect your network by filtering traffic and blocking outsiders from gaining unauthorized access to the private data on your computer.

Not only does a firewall block unwanted traffic, it can also help block malicious software from infecting your computer.

Firewalls can provide different levels of protection. How much protection you need may vary.

This article can help you learn what firewalls do on a basic level.

What is network security?

Firewalls represent a first line of defense in home network security.

Your home network is only as secure as its least protected device. That’s where a network security system comes in.

A firewall shouldn’t be your only consideration for securing your home network. It’s important to make sure all of your internet-enabled devices — including mobile devices — have the latest operating system, web browsers, and security software.

Another consideration? Securing your wireless router. This might include changing the name of your router from the default ID and password it came with from the manufacturer, reviewing your security options, and setting up a guest network for visitors to your home.

What does a firewall do?

A firewall acts as a gatekeeper. It monitors attempts to gain access to your operating system and blocks unwanted traffic or unrecognized sources.

Your operating system and your security software usually come with a pre-installed firewall. It’s a good idea to make sure those features are turned on, and that your security settings are configured to run updates automatically.

Do I need a firewall to be safe online?

You might already engage in certain safe computer and Internet use practices, including these:

  • You don’t click on unknown links or attachments.
  • You only log on to trustworthy, known websites.
  • You never give out any personal information.
  • You have strong, unique, complex passwords that you update often.

Does that make you safe enough? The answer may be “no.” If you use the Internet, it’s smart to have a firewall in place. Cyberthreats are widespread and evolving. It’s important to use available defenses to help protect your network, and the personal information stored on your computer, against cybercrimes.

What are the main risks of not having a firewall? Here are three.

Open access

Without a firewall, you’re accepting every connection into your network from anyone. You wouldn’t have any way to detect incoming threats. That leaves the door open for malicious users.

Lost or compromised data

Not having a firewall could lead to someone gaining control over your computer or network. Cybercriminals could delete your data. Or they could use it to commit identity theft or financial fraud.

Network crashes

Without a firewall, attackers could shut down your network. Getting it running again, and attempting to recover your stored data, could involve your time and money.

Help take back control of your online privacy.

With the Norton Privacy Manager app, it’s easy to be smart and secure about what information you share online.


Editorial note: Our articles provide educational information for you. Norton LifeLock offerings may not cover or protect against every type of crime, fraud, or threat we write about. Our goal is to increase awareness about cyber safety. Please review complete Terms during enrollment or setup. Remember that no one can prevent all identity theft or cybercrime, and that LifeLock does not monitor all transactions at all businesses.

Norton by Symantec is now Norton LifeLock. LifeLock™ identity theft protection is not available in all countries.

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