How Walls, Concrete, and Steel Affect Your Signal

The matter of how far your network adapter's radio signal will travel varies greatly depending on the layout of your home or office. Here are a few considerations to keep in mind while you design your wireless LAN.

The signal of wireless network adapters does not require that the network adapters have a direct line of sight between them. The signal bounces off objects and can pass through walls. That said, it is important to keep in mind that:

Concrete and steel will seriously degrade the signal.
Glass, to a lesser extent, will also weaken the signal.
Books and other solid objects often found on a desk, if covering the adapter, will degrade the signal significantly.

All wireless network adapters come with software that will tell you the strength of the signal, often with a visual representation on your desktop (see Figure 3.6). As you move your equipment around your home or office you can easily see how strong your signal is. The signal is shown as a percentage, and often also is represented by a color , with green showing an " excellent " signal, yellow being a "fair" signal, and a red indicator showing no link to the network. We talk more about working with this software in Chapter 4.

Figure 3.6. Network adapters often come with software to measure the strength of your wireless signal. At the bottom right of the screen, an icon shows the wireless network adapter is receiving a signal.

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Now we'll consider how the speed your software displays translates to what you'll actually get.