What is a Firewall?

We have all seen the “Warning – Intrusion Attempt – Your Computer is being hacked” alerts. Many people believe this means someone is attempting to access their computer; however, what it probably means is that an infected computer that is configured to access any vulnerable computer is trying to invade yours. A computer virus spreads just like a regular virus. The more computers it can access, the better. The above warning that you have seen is your firewall doing its job – protecting your computer!

There are two kinds of firewalls: software firewalls and hardware firewalls. A firewall protects your computer from network-based threats. Almost all computers connected to the internet are under constant attack. 

Some symptoms of an attack are

• a sluggish and slow computer response.
• the computer screen or mouse pointer flickering.
• the occurrence of extra installed programs that you yourself did not install.
• that your homepage has changed, and you yourself did not change it.
• when shortcuts appear on your desktop or system tray that you yourself did not place there.
• automatically disabled security tools that are unable to be restarted.

Software firewalls usually come standard on a computer but even with software firewalls, these attacks can occur. There are additional steps you can take to protect your computer further. Consider a NAT router with hardware firewall. The router’s job is to “route” data between computers. NAT routers allow you to share a Network Address Translation connection. What this means is that when your computer initiates a connection on the internet, the router keeps track so that when a response is returned to your connection, it knows where to send it. Without your computer initiating the connection, the router will not recognize an inbound attempt; therefore, it doesn’t know where to send the connection, thereby being forced to ignore the attempt and block all inbound attempts that you did not initiate.

Software firewalls can provide additional protection from computers on your own local network, and together, hardware and software firewalls can perform complimentary functions that when used together will give you a greater degree of protection than either one alone. Be advised that a firewall of any kind will not protect you from threats that you invite onto your machine yourself, such as in email, attachments, downloads, and removable hard drives.

Many broadband internet connections have a NAT router, but it’s important to be sure yours does. Contact your computer services specialist to determine if you are behind a NAT firewall, or if you need additional protection.