Connecting to the Internet

Universities and large companies are most likely connected to the Internet via high-speed wiring that transmits data very quickly. As the Internet continues to explode around the world, several high-speed connection options are becoming more available and affordable for business and home use: DSL (Digital Subscriber Lines), wires that provide a completely digital connection; and cable modems, which use cable television lines. DSL and cable modems, also known as broadband connections, are continually turned on and connected and use a network setup. If a broadband connection is not available, you need to establish a connection over a phone line using a dial-up modem. Data travels more slowly over phone lines than over digital lines and cable modems. Whether you use a phone line, a DSL line, or a cable modem, Windows can help you establish a connection between your computer and the Internet using the Connect to the Internet wizard. First, you need to select an ISP (Internet Service Provider), which is a company that sets up an Internet account for you and provides Internet access. ISPs maintain servers connected directly to the Internet 24 hours a day. You pay a fee, sometimes by the hour, but more often a flat monthly rate. To connect to the Internet, you need to obtain an Internet account and connection information from your ISP or your system administrator. For details, see “Creating an Internet Connection” on page 136. If you are working on a network, you can also share one Internet connection with everyone. For information on creating an Internet Connection Sharing (ICS), see “Sharing an Internet Connection” on page 378.

Protecting your Computer with a Firewall

When you connect to the Internet, you can access Web sites on the Internet, but other users on the Internet can also access information on your computer and potentially infect it with harmful viruses and worms. For more information, see “Avoiding Viruses and Other Harmful Attacks” on page 330.

You can prevent this by activating Windows Firewall, another security layer of protection. A firewall is a security system that creates a protective barrier between your computer or network and others on the Internet. Windows Firewall monitors all communication between your computer and the Internet and prevents unsolicited inbound traffic from the Internet from entering your computer. Windows Firewall blocks all unsolicited communication from reaching your computer unless you specifically allow it (unblock) to come through, known as an exception. For example, if you run a program, such as Windows Messenger that needs to receive information from the Internet or a network, Windows Firewall asks if you want to block or unblock the connection. If you choose to unblock it, Windows Firewall creates an exception so the program can receive information. For details, see “Setting Up Windows Firewall” on page 137.

If you send and receive e-mail, Windows Firewall doesn’t block spam or unsolicited e-mail or stop you from opening e-mail with harmful attachments. To protect your computer from these attacks, see “Protecting Against E-mail Attacks” on page 345. Windows Firewall helps block viruses and worms from reaching your computer, but it doesn’t detect or disable them if they are already on your computer or come through e-mail. To protect your computer, you need to install antivirus software.