Just as you wouldn’t leave your windows and doors open when you leave the house, you shouldn’t leave your computer wide open to the internet. By default, the Windows Firewall will be turned on in a new Windows 8 installation. The firewall blocks access from the internet into your computer. You’ll still be able to go from your computer out to the internet, but not the other way around. Windows XP machines were notoriously insecure – so much so that without a firewall in place, a newly installed XP machine (unpatched) could be compromised in 5-10 minutes. The firewall blocks those incoming attacks or traffic to keep your machine safe.
You can find the Windows Firewall by using the Search Charm and searching for “firewall”. When you open it, make sure that it is enabled for any network connections you currently have active (Figure 2).
If you need to allow an application to communicate with your computer from the internet, you can enable exceptions. Just click Allow an App or Feature through Windows Firewall and select the application you want to give access to (Figure 3).
If you don’t see your application listed, you may need to go to the Advanced view. To do this, go back to the main Firewall page and click Advanced Settings. The Windows Firewall with Advanced Security window will open. (Figure 4). From here you can click on Inbound Rules -> New Rule to define a custom rule.
These are just a few of the security tools built in to Windows 8. It’s nice that Microsoft gives you free alternatives to some of the expensive third-party security suites out there. The built in tools may not have as many bells and whistles as the third-party suites, but they do their job pretty well.