180 Part III: Installing a Wireless Network

Windows XP

To set up Internet connection sharing in Windows XP:

1.Choose Start Control Panel.

2.Double-click the Network Connections icon in the Control Panel to display the Network Connections window.

3.Highlight the Network Connection item for the network device that you want to use to connect to the Internet and then choose File Properties.

The Local Area Connection Properties dialog box appears.

4.On the Advanced tab, select the Allow Other Network Users to Connect through This Computer’s Internet Connection check box, as shown in Figure 9-12.

By default, the Allow Other Network Users to Control or Disable the Shared Internet Connection check box is selected. Unless you want other users on the network to be able to enable and disable the shared connection, clear this check box. For dialup modems, you can also cause the modem to dial automatically when another computer on the network attempts to access the Internet.

Using the same process as above on your dialup networking connection, select the Establish a Dial-up Connection Whenever a Computer on My Network Attempts to Access the Internet check box. Then click OK. See Figure 9-12.

You’re returned to the Network Connections window.

Figure 9-12:

Enable

Internet connection sharing in Windows XP.

Chapter 9: Setting Up Internet Sharing 181

5.Close the Network Connections window.

When you complete these steps, this Windows XP PC is now both a DHCP server and a NAT server, equivalent to a broadband router. You might need to restart any PC or AP that is connected to the PC for the IP addresses to be reassigned.

To remove Internet connection sharing, display the Advanced tab of the

Local Area Connection Properties dialog box and clear Allow Other Network

Users To Connect through This Computer’s Internet Connection check box.

Mac OS X v. 10.2 (Jaguar)

To set up Internet connection sharing in Mac OS X v. 10.2 or later:

1.From the Apple menu, click System Preferences to display the System Preferences pane.

2.Click the Sharing icon in the System Preferences panel to display the Sharing panel.

If you don’t see the Sharing icon, click the Show All button on top of the System Preferences pane, and it will appear.

3.Click the Internet tab, as shown in Figure 9-13.

Figure 9-13:

The Internet

tab in the

Sharing

pane of

Mac OS X.

Chapter 10

Securing Your Wireless Home

Network

In This Chapter

Worrying about wireless home network security

Understanding Wired Equivalent Privacy (WEP)

Getting security on your network

Checking out future security enhancements

If you read the news — well, at least if you read the same networking news sources that we do — you’ve probably seen and heard a thing or two (or a hundred) about wireless local area network (LAN) security. In fact, you really don’t need to read specialized industry news to hear about this. Many major

newspapers and media outlets — The New York Times, the San Jose Mercury News, and USA Today, among others — have run feature articles documenting the insecurity of wireless LANs. Most of these stories have focused on wardrivers, those folks who park in the lot in front of an office building,

pull out their laptops, and easily get onto corporate networks.

In this chapter, we talk a bit about these security threats and how they might affect you and your wireless home network. We also (being the helpful types that we are) give you some good advice on how you can make your wireless home network more secure. And finally, we talk about some new solutions that are being developed by the wireless LAN industry to beef up wireless LAN security.

The advice that we give in this section applies equally to your wireless network, whether it uses 802.11b, a, or g. We’re not going to be specific to any particular 802.11 technology in this chapter because the steps that you take to batten down the hatches on your network are virtually identical, regardless of which version of 802.11 you choose. (If you’ve missed our discussion on 802.11 basics, jump back to Chapter 2.)