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Minasi c01.tex V3 - 05/29/2008 9:45pm Page 9
WHAT’S THE POINT OF NETWORKS AND NETWORKING? 9
provide a connection. In some cases, such as a small network that has a server and only a
few devices, using standard devices may actually prove less expensive in the long run. Most
routers support only two networks. However, it’s possible to find routers that support more —
all the way up to 128 networks — but you’ll pay a hefty price for them.
Wireless Access Point A wireless access point (WAP) is a type of router. It creates a connec-
tion between a wired network and wireless devices. The wireless devices use radio waves to
communicate with the WAP. As with most network devices, you plug the WAP into a hub,
switch, or router to create the connection to the wired network. The critical consideration for
a WAP is the standards to which the WAP adheres. For example, if your laptop provides an
802.11g connection, then your WAP must support the 802.11g specification or the two devices
won’t communicate with each other. The 802.11b and 802.11g specifications are the most com-
mon in use today, but you must check your wireless devices to determine which standard they
follow. In some cases, the WAP will support multiple standards. You’ll want all your wireless
devicestousethesamestandardbecausesomewireless connection standards don’t work well
with others because of radio wave interference. Another consideration is the antenna range for
the WAP. This range determines the maximum distance that can separate the wireless device
and the WAP. Always remember that the distance between the wireless device and the WAP
affects transmission speed. You may think that you’ll get 54 Mbps transmission speed, but you
won’t when you’re at the maximum distance. In fact, most WAPs provide multiple fallback
speeds so you need to know the slowest speed you can expect before losing the connection
completely.
It often helps to view network diagrams put together by other people before you create
your own network. For example, you can see a basic home network with a WAP at
http://www.homenethelp.com/web/diagram/wireless-bridge-xp.asp. The diagrams at
http://msdn2.microsoft.com/en-us/library/aa934598.aspx show you how you might
attach a network-ready device. The diagram at http://www.weresc.com/home.php is signifi-
cantly more complex than the other two, but it shows you that networks can be any size. If you
want to create your own network diagram using the hardware discussed in this chapter, check
out the free program at http://www.supershareware.com/info/edraw-network-
diagrammer.html.
After you look at a number of designs put together by other people, you’ll want to spend some
time creating your own diagram. The diagram need not be very complicated. However, you need
to provide enough information to ensure you can create a good network setup. Figure 1.2 shows a
network diagram that includes many of the elements that you’ll probably have on your network.
This diagram doesn’t represent your network any more than the diagrams I referenced earlier
through Web sites — it’s just another example that you can use to create your own diagram.
This diagram shows a number of important features. Every computer and network-ready
device can have a NIC that is separate from that device. Yes, the NIC appears inside the unit,
but it may not come with the unit — you may have to purchase this item separately and ask the
vendor to install it for you. The connector (shown in Figure 1.1) will appear somewhere on the
case. You connect a cable from the device to the hub or switch as shown. In some cases, you might
actually connect the computers and network-ready devices directly to the router, instead of using
a separate connection as shown. Notice that the router provides a connection to the Internet — the
hub or switch won’t provide this connection.
Do you see that lightning bolt next to the WAP? That lightning bolt represents a connection
made using radio waves — a wireless connection. Any device, such as a laptop, designed to use
the wireless standard supported by the WAP can connect to the network through the WAP as
shown. You shouldn’t add a WAP to your network unless you actually need it because a WAP can