Start by turning on the firewall features on your computer and/or PCs, or consider a stand-alone firewall program.
What is a firewall? The definition is burrowed from the building industry. As the name implies, a firewall is a barrier between two things. In this case, your computer and the Internet. Nasties from the Internet side of the wall are prevented from affecting your computer. Many users are generally unaware both your router and your operating system (from Windows XP and Apple OSx onwards) have built in firewall. Make sure these are turned on. To do so consult your computers and routers documentation.
Note: If you have a commercial security program installed on your computer with the stated term Internet security a sofware firewall is part of the application. To setup a thrid party security application firewall consult application documentation.
If you don’t have a thrid party security application Microsoft Technet article “How to Configure Windows Firewall” on a Single Computer explains how to configure a Windows operating system firewall. All Windows software from Windows XP service pack 2 onwards (Vista, Windows 7) offers a firewall software feature.
If you have an Apple OSx computer then refer to Apples technology called “Application Firewall” article to set-up Apples firewall.
Configuring your router’s firewall refer to manufactures documentation and or website.
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