Click Add. The larger Printer List dialog box disappears and the smaller Printer List dia-

Part IV ✦ Adding the Internet, E-Mail, and an Intranet Figure 16-7: ISPs feed into larger ISPs, which feed into larger ISPs, and all together, these servers form the Internet. Sharing Internet Connections Dial-up modems are not shareable over a local area network under normal conditions. With the use of a third-party application, however, you can surf the Net and send and receive e-mail at the same time others on the network use the Internet connection. Various programs exist, often called proxy servers, which enable you to turn one phone line into multiple Internet connections. Many people use cable modems or DSL modems in their home or small business for Internet connections instead of using dial-up modems. You can also use a software program or a hard- ware device, often called firewall routers, to share these modems. Basically, these applications or devices enable all computers on a LAN to connect to the Internet, surf the Web, and send and receive e-mail simultaneously, using one Internet connection. Some ISPs have policies against sharing an Internet connection. Check with your ISP for more information. When using the proxy applications, you usually have to install TCPIP to each computer on the LAN. Additionally, you install the proxy software on the host, or server, machine first; this is the computer that’s attached directly to the dial-up or cableDSL modem. Then you install the software on client or guest machines. Tip Internet Cable modem Cable company Chapter 16 ✦ Accessing the Internet If you use a hardware device, all computers connect to the device, through a hub or switch for example, so each computer is connected to the Internet all the time. Among the hardware devices previously mentioned for firewall use, many can be used for Internet sharing as well. A few more are described in this section. Using software to share a connection One of the most popular programs on the market is WinGate. WinGate has been in use for many years as a low-cost standard for Internet connection sharing, and with each new ver- sion, it improves. WinGate now offers an antivirus program, content filtering, and e-mail server, and a VPN solution for about 50. WinGate supports dial-up connections, cable modems, satellite, DSL, T1, and so on. It also supports many Internet applications. WinGate includes a proxy server you can configure for various protocols, and it’s also equipped with a firewall to protect your system from hackers. WinGate supports NAT. WinGate, by Deerfield.com, costs around 50 for a three-user version, 100 for six-user, and the more users you add, the higher the cost. Microsoft has included ICS Internet Connection Sharing with Windows 2000 and XP. ICS enables the computers on the LAN to share an Internet connection. Any operating system can connect through ICS as long as the computer uses TCPIP. ICS may not work with some cable modems or other return network telco devices. Telcos are connections that receive data through a NIC attached to a cable modem, and transmit data through a telephone line attached to a dial-up modem. Check Microsoft if you’re unsure. Tip Network Address Translation NAT Network Address Translation NAT is an Internet standard that enables a LAN to use one set of IP addresses for internal traffic and a second set of addresses for external traffic. NATs are a type of software application that lets multiple computers access the Internet. NATs are available for most Windows OSs and for many Mac OSs, although selection is limited for Macs. The advantages of using NAT-enabled applications are as follows: ✦ Computers with NATs handle multiplayer Web gaming well. ✦ NATs are easier to set up than proxies. ✦ They can be expanded to handle many computers. Disadvantages include the following: ✦ The computer running the NAT program must be running for other computers to access the Internet. ✦ Managing the access isn’t as flexible as proxies. ✦ NATs don’t support all applications, so adding services can be difficult. Part IV ✦ Adding the Internet, E-Mail, and an Intranet ICS isn’t a full-feature program; other programs offer more. For example, ICS doesn’t support access controls or logging. For more information about ICS, see www.microsoft.com or www.practicallynetworked.com. For the Macintosh, IPNetRouter by Sustainable Softworks is an easy way to share a dial-up, cable, or DSL modem Internet connection. IPNetRouter is a router and firewall and uses NAT and IP filtering. The cost of IPNetRouter is around 90. WinProxy is another software program that enables you to share a high-speed Internet con- nection. WinProxy also supports dial-up modems, cableDSL modems, satellite, T1 and T3, wireless, and other connections. WinProxy is also a firewall, enabling you to block access to sites, and it includes antivirus support. WinProxy is made by Blue CoatOsitis and costs around 60 for a three-user version or 100 for a five-user version. You can buy many other software programs to share an Internet connection, many of which are also firewalls or proxy servers. Some other products include SolidShare, as well as ezProxy from LavaSoftware. Using hardware to share a connection As previously mentioned, you can often use firewall routers to share an Internet connection. Just as you would connect the router to use for a firewall, you would connect the device to use for Internet sharing. You use the hardware router as a bridge between the modem dial- up, cable, DSL, and so on and the hub or switch you use to network your computers. Some routers you use for sharing a connection are also Ethernet hubs or switches, which means you combine two functions into a single device. In this case, you connect the modem to the Ethernet routerhubswitch, and the computers connect to the routerhubswitch as well. See Chapter 9 for more information. Linksys makes a cableDSL modem four-port router you can use to connect your computers to one Internet connection. For about 50, you can get a 10100 Ethernet router that also acts as a rudimentary firewall. NAT is also handled by the Linksys box. Zoom makes an Internet Gateway for around 60. All computers on the network share one Internet connection through a DSL modem, a cable modem, or an analog dial-up modem using NAT. Computers share one Internet IP address while retaining their individual IP addresses. LAN connections are through 10100 Ethernet. You can plug another hub into the gateway so that more computers are supported. NETGEAR also makes a similar product, as do Asante, Black Box, and Hawking. You can also use wireless routers. Additionally, you can connect various operating systems to these routers with no problem in sharing the Internet connection. Contracting a Service Provider In today’s market, you can find many providers of Internet services. Commercial online services, such as Prodigy and America Online, offer Internet access plus online shopping, groups, games, and file libraries. They even offer free browsers and e-mail programs for download. Chapter 16 ✦ Accessing the Internet Working with Web Browsers and E-Mail The Web browser and e-mail program you use on your computers in the network both should be programs with which you’re comfortable. A Web browser is a program that enables you to view pages on the Internet in the special Hypertext Markup Language HTML format. A browser also enables you to control how the Web pages appear and how the graphic images look, and it enables you to jump from link to link while surfing the Web. An e-mail program might be a separate application or be connected to your browser. The e-mail program enables you to send and receive messages over the Internet. You should use the same browser and e-mail programs on all computers on the network, if possible. Troubleshooting problems, upgrading versions, and maintaining the programs are easier for you if all the applications are the same brand and version. Also, compatibility issues are easier to deal with when you keep all the Internet programs the same on your computers. If you’re using Windows, Internet Explorer is built into the program. You may prefer to use Netscape or some other application. The program you choose depends on your preferences and will not affect sharing an Internet connection or account, as described earlier in this chapter. Figure 16-8 illustrates Microsoft Internet Explorer. The Web browser enables you to view Web pages, navigate the Web easily, search for certain topics, and more. Internet service providers, however, may provide more services for less than the commercial online services. An ISP provides you with a connection to the Internet, mailboxes, space on the server for a Web page or Web site, access to news servers, and more. Before you sign up for ser- vices with an ISP, however, you should consider a few things and understand that local ISPs are not always the best solution. ✦ Ask your friends which ISP they use and how satisfied they are with the service. Ask if the ISP is reliable, if the ISP has a lot of hardware problems, and if technical support is helpful. ✦ Find out prices. Ask whether there’s a limit on connect time or if time and usage are unlimited. Ask if they include Web page space and any other perks. ✦ You also should consider how long the ISP has been in business. New ISPs pop up all the time, but are not always prepared to handle the job. Most new ISPs don’t start with enough modems and connections, so they must upgrade within a few months. Others don’t have a business plan and the business sinks after only a few months. Find an established ISP for your Internet connection. ✦ Local, regional, and national providers are available. Find out if there’s a local access number for dial-up, or at least an 800 number that will cost less than long-distance con- nections. Also, your cable company provides ISP services, as does a phone company from whom you can get DSL services.