Windows 8.1 Bible

Chapter 7: Protecting Yourself with Windows Firewall

IN THIS CHAPTER

Understanding how firewalls protect your computer

Using Security Center

Using Windows Firewall

Configuring Windows Firewall

If you use the Internet, a firewall is a must-have security tool. It's not the only tool you need, but it's an important one. It protects your computer from hackers and worms. Hackers are people who would attempt to access your computer through the Internet without your knowing it. Worms are programs, such as viruses, that are usually written to do intentional harm.

Windows 8.1 comes with its own built-in firewall. If you didn't know about it before going online, relax. It's enabled by default. So, most likely, it's been protecting you since the very first moment you went online. (Plus, your Internet service provider protects you from most invasions.) In this chapter, you learn how the firewall works and how to configure it for maximum protection.

How Firewalls Work

To understand what a firewall is, you need to first understand what a network connection is. Even though you have only one skinny set of wires connecting your computer to the Internet (through a DSL phone line or cable outlet), that connection actually consists of 65,535 ports. Each port can simultaneously carry on its own conversation with the outside world. So, theoretically, you could have 65,535 things going on at a time. Of course, nobody ever has that much going on all at one time. A handful of ports is more like it. ...