Home Networking: The Missing Manual

Wireless Networks

Wired networks have lots of advantages, but they can require enough wiring to reach Mars—and they keep you chained to your nearest network connection. Enter wireless networking, which uses radio signals instead of cables to transmit data. It can be a handy alternative to having your desk chair get tangled in a mass of Ethernet cable spaghetti, and it lets you roam as far as your signals reach, like out under the shade of a tree on a nice summer day. In addition, if you have a laptop that's ready for wireless, you can hop online at an ever-growing number of places—known as WiFi zones or hot spots—that broadcast Internet signals, like airports, public parks, and trendy coffee shops.

Note

Engineers, when not making up complicated names for things, develop wireless networking technology according to a series of rules. An international association—the Institute of Electrical and Electronics Engineers, known as IEEE (pronounced "eye triple E")—creates those rules, or standards, which specify how wireless devices work: what part of the radio spectrum they use and how they talk to each other. "WiFi" refers to the predominant family of wireless standards.

To set up a wireless network, you need a wireless router or base station (the term Apple prefers), which broadcasts your network traffic (including your Internet connection), over the airwaves. Depending on the type of wireless technology inside, wireless routers usually beam their signals over an area of about 50 to 150 square feet. Any computer with a wireless network adapter (Section 3.3.4) can join the network. Figure 1-5 shows you how it works.

Figure 1-5. Your broadband modem plugs into the wireless router. Computers outfitted with wireless adapter cards can access the network and communicate with both the Internet and each other.

While WiFi offers terrific convenience, it does have a few disadvantages. It's not as fast as old, wired Ethernet; 54 Mbps is the current speed limit. Configuring the system can be tricky (but Chapter 3 is here to guide you through the process). And interference from other devices that use radio waves, such as cordless phones and microwave ovens, can drag down and diminish the stability of your network.

In fact, radio waves from your neighbors' wireless networks can interfere with your system. And physical objects or barriers like pipes or thick walls can also degrade your signal. Finally, while no network is airtight, wireless networks can be especially susceptible to hackers if you don't set up some safeguards. (Section 3.6 tells you how to dig the virtual moat and pull up the digital drawbridge around Castle Wireless Network)

UP TO SPEED: Up to Speed?

Most people have "the need, the need for speed," but when it comes to home networking, there are two different aspects of speed to clock.

First, there's the speed of your Internet connection. If you have broadband cable or DSL service, your connection speed probably tops out at around 1.5 megabits per second (see that box way back yonder on Section 1.3 if this megabit stuff isn't ringing a bell). Think of this as your outside connection, because it's the link between your personal network and the vast world out there on the Internet.

But then there's also the speed of your internal network inside the house. This is the rate at which you can transfer files such as Word documents, songs, and movies between the computers connected to your home network.

The internal network speed depends on what type of networking technology you use—and it can run anywhere from 11 Mbps to 1,000 Mbps. (Both wired and wireless networks come in different varieties, all of which have different speeds.) But regardless of the type of network you choose, you can surf the Web and send email only at the speed of your broadband connection.

If you intend to use your network only for common online tasks like surfing the Web and sending email, then all the available network technologies will meet your needs because they're faster than the Internet connection you already have. But if you want to use your network to stream Hulk-size movie and music files to your wireless home-entertainment center, your internal network speed becomes much more important.

The one rare exception is if you happen to be among the lucky few with a super-speedy Internet connection, such as a T-3 line or a fiber-optic link, which offer speeds from as fast as your typical cable modem to as fast as NASA's supercomputers. In these cases, make sure you pick a networking technology that isn't slower than your Internet connection.